Abrasive article and method of forming

ABSTRACT

An abrasive article includes a substrate having an elongated body, a plurality of discrete tacking regions defining a discontinuous distribution of features overlying the substrate, where at least one discrete tacking region of the plurality of discrete tacking regions includes a metal material having a melting temperature not greater than 450° C., a plurality of discrete formations overlying the substrate and spaced apart from the plurality of discrete tacking regions, and a bonding layer overlying the substrate, plurality of discrete tacking regions, and plurality of discrete formations.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application is a continuation of and claims priority to U.S.patent application Ser. No. 15/840,003, filed Dec. 13, 2017, entitled“ABRASIVE ARTICLE AND METHOD OF FORMING,” naming as inventors YinggangTian et al, which is a continuation of and claims priority to U.S.patent application Ser. No. 15/195,236, filed Jun. 28, 2016, entitled“ABRASIVE ARTICLE AND METHOD OF FORMING,” naming as inventors YinggangTian et al., now U.S. Pat. No. 9,878,382, which claims priority under 35U.S.C. § 119(e) to U.S. Provisional Patent Application No. 62/186,225,filed Jun. 29, 2015, entitled “ABRASIVE ARTICLE AND METHOD OF FORMING,”naming as inventors Yinggang Tian et al., which applications areassigned to the current assignee hereof and are incorporated byreference herein in their entireties.

BACKGROUND

The following is directed to methods of forming abrasive articles, andparticularly, single-layered abrasive articles.

DESCRIPTION OF THE RELATED ART

A variety of abrasive tools have been developed over the past centuryfor various industries for the general function of removing materialfrom a workpiece, including for example, sawing, drilling, polishing,cleaning, carving, and grinding. In particular reference to theelectronics industry, abrasive tools suitable for slicing crystal ingotsof material to form wafers is particularly pertinent. As the industrycontinues to mature, ingots have increasingly larger diameters, and ithas become acceptable to use loose abrasives and wire saws for suchworks due to yield, productivity, affected layers, dimensionalconstraints and other factors.

Generally, wire saws are abrasive tools that include abrasive particlesattached to a long length of wire that can be spooled at high speeds toproduce a cutting action. While circular saws are limited to a cuttingdepth of less than the radius of the blade, wire saws can have greaterflexibility allowing for cutting of straight or profiled cutting paths.

Various approaches have been taken in conventional fixed abrasive wiresaws, such as producing these articles by sliding steel beads over ametal wire or cable, wherein the beads are separated by spacers. Thesebeads may be covered by abrasive particles which are commonly attachedby either electroplating or sintering. However, electroplating andsintering operations can be time consuming and thus costly ventures,prohibiting rapid production of the wire saw abrasive tool. Most ofthese wire saws have been used in applications, where kerf loss is notso dominating as in electronics applications, often to cut stone ormarble. Some attempts have been made to attach abrasive particles viachemical bonding processes, such as brazing, but such fabricationmethods reduce the tensile strength of the wire saw, and the wire sawbecomes susceptible to breaking and premature failure during cuttingapplications under high tension. Other wire saws may use a resin to bindthe abrasives to the wire. Unfortunately, the resin bonded wire sawstend to wear quickly and the abrasives are lost well before the usefullife of the particles is realized, especially when cutting through hardmaterials.

Accordingly, the industry continues to need improved abrasive tools,particularly in the realm of wire sawing.

SUMMARY

According to a first aspect, an abrasive article includes a substratecomprising an elongated body, a plurality of discrete tacking regionsdefining a discontinuous distribution of features overlying thesubstrate, wherein at least one discrete tacking region of the pluralityof discrete tacking regions comprises a metal material having a meltingtemperature not greater than 450° C., a plurality of discrete formationsoverlying the substrate and spaced apart from the plurality of discretetacking regions, and a bonding layer overlying the substrate, pluralityof discrete tacking regions, and plurality of discrete formations.

In yet another aspect, an abrasive article includes a substrateincluding an elongated body, a plurality of discrete tacking regionscomprising a metal material overlying the substrate, wherein eachdiscrete tacking region is isolated from another discrete tacking regionand at least one abrasive particle is associated with each discretetacking region, and a bonding layer overlying the plurality of discretetacking regions, the at least one abrasive particle and in directcontact with at least a portion of the substrate.

For another aspect, an abrasive article includes a substrate comprisingan elongated body, a plurality of discrete tacking regions overlying thesubstrate and defining gap regions between each of the discrete tackingregions of the plurality of discrete tacking regions, abrasive particlesoverlying the plurality of discrete tacking regions, and a plurality ofdiscrete formations overlying the substrate and spaced apart from theplurality of discrete tacking regions and the abrasive particles.

In another aspect, a method of forming an abrasive article includestranslating a substrate having an elongated body through a mixtureincluding abrasive particles and a particulate including a tackingmaterial, attaching at least a portion of the abrasive particles andpowder material to the substrate, and treating the substrate to form anabrasive article preform including a plurality of discrete tackingregions overlying the substrate and defining gap regions between each ofthe discrete tacking regions of the plurality of discrete tackingregions, abrasive particles overlying the plurality of discrete tackingregions, and a plurality of discrete formations overlying the substrateand spaced apart from the plurality of discrete tacking regions and theabrasive particles.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be better understood, and its numerousfeatures and advantages made apparent to those skilled in the art byreferencing the accompanying drawings.

FIG. 1 includes a flow chart providing a process for forming an abrasivearticle in accordance with an embodiment.

FIG. 2A includes an illustration of a process for forming an abrasivearticle in accordance with an embodiment.

FIG. 2B includes an illustration of a portion of the process of formingan abrasive article in accordance with an embodiment.

FIG. 3 includes an illustration of a portion of an abrasive article inaccordance with an embodiment.

FIG. 4 includes an image of a portion of an abrasive article accordingto an embodiment.

FIG. 5 includes a cross-sectional image of a portion of the abrasivearticle of FIG. 4.

FIG. 6 includes a cross-sectional image of a portion of the abrasivearticle of FIG. 4.

FIG. 7A includes a cross-sectional image of a portion of a comparativeabrasive article.

FIG. 7B includes a cross-sectional image of a portion of an abrasivearticle according to an embodiment.

FIG. 8 includes an illustration of the experimental setup for a coatingadhesion test.

FIG. 9A includes an image of a portion of a comparative abrasivearticle.

FIG. 9B includes an image of a portion of an abrasive article accordingto an embodiment.

FIG. 10 includes a plot the steady state wire bow for a sample abrasivewire formed according to an embodiment and a comparative abrasivearticle.

FIG. 11A includes an image of a portion of a comparative abrasivearticle.

FIG. 11B includes an image of a portion of an abrasive article accordingto an embodiment.

FIG. 12 includes an image of a portion of an abrasive article accordingto an embodiment.

DETAILED DESCRIPTION

The following is directed to abrasive articles, and particularlyabrasive articles suitable for abrading and sawing through workpieces.In particular instances, the abrasive articles herein can form wiresaws, which may be used in processing of sensitive, crystallinematerials in the electronics industry, optics industry, and otherassociated industries.

FIG. 1 includes a flow chart providing a process of forming an abrasivearticle in accordance with an embodiment. The process can be initiatedat step 101 by providing a substrate. The substrate can provide asurface for affixing abrasive materials thereto, thus facilitating theabrasive capabilities of the abrasive article.

In accordance with an embodiment, the process of providing a substratecan include a process of providing a substrate having an elongated body.In particular instances, the elongated body can have an aspect ratio oflength:width of at least 10:1. In other embodiments, the elongated bodycan have an aspect ratio of at least about 100:1, such as at least1000:1, or even at least about 10,000:1. The length of the substrate canbe the longest dimension measured along a longitudinal axis of thesubstrate. The width can be a second longest (or in some cases smallest)dimension of the substrate measured perpendicular to the longitudinalaxis.

Furthermore, the substrate can be in the form of elongated body having alength of at least about 50 meters. In fact, other substrates can belonger, having an average length of at least about 100 meters, such asat least about 500 meters, at least about 1,000 meters, or even at leastabout 10,000 meters.

Furthermore, the substrate can have a width that may not be greater thanabout 1 cm. In fact, the elongated body can have an average width of notgreater than about 0.5 cm, such as not greater than about 1 mm, notgreater than about 0.8 mm, or even not greater than about 0.5 mm. Still,the substrate may have an average width of at least about 0.01 mm, suchas at least about 0.03 mm. It will be appreciated that the substrate canhave an average width within a range between any of the minimum andmaximum values noted above.

In certain embodiments, the elongated body can be a wire having aplurality of filaments braided together. That is, the substrate can beformed of many smaller wires wound around each other, braided together,or fixed to another object, such as a central core wire. Certain designsmay utilize piano wire as a suitable structure for the substrate. Forexample, the substrate can be a high strength steel wire having a breakstrength of at least about 3 GPa. The substrate break strength can bemeasured by ASTM E-8 for tension testing of metallic materials withcapstan grips. The wire may be coated with a layer of a particularmaterial, such as a metal, including for example, brass. Still, in otherinstances, the wire may be essentially free of any coatings on theexterior surface.

The elongated body can have a certain shape. For example, the elongatedbody can have a generally cylindrical shape such that it has a circularcross-sectional contour. In using elongated bodies having a circularcross-sectional shape, as viewed in a plane extending transversely tothe longitudinal axis of the elongated body.

The elongated body can be made of various materials, including forexample, inorganic materials, organic materials (e.g., polymers andnaturally occurring organic materials), and a combination thereof.Suitable inorganic materials can include ceramics, glasses, metals,metal alloys, cermets, and a combination thereof. In certain instances,the elongated body can be made of a metal or metal alloy material. Forexample, the elongated body may be made of a transition metal ortransition metal alloy material and may incorporate elements of iron,nickel, cobalt, copper, chromium, molybdenum, vanadium, tantalum,tungsten, and a combination thereof.

Suitable organic materials can include polymers, which can includethermoplastics, thermosets, elastomers, and a combination thereof.Particularly useful polymers can include polyimides, polyamides, resins,polyurethanes, polyesters, and the like. It will further be appreciatedthat the elongated body can include natural organic materials, forexample, rubber.

Furthermore, the abrasive articles herein can form a substrate having acertain resistance to fatigue. For example, the substrates can have anaverage fatigue life of at least 300,000 cycles as measured through aRotary Beam Fatigue Test or a Hunter Fatigue Test. The test can be aMPIF Std. 56. The rotary beam fatigue test measures the number of cyclesup to wire break at designated stress (e.g. 700 MPa), i.e. constantstress or the stress under which the wire was not ruptured in a cyclicfatigue test with a number of repeating cycles of up to 10⁶ (e.g. stressrepresents fatigue strength). In other embodiments, the substrate maydemonstrate a higher fatigue life, such as least about 400,000 cycles,at least about 450,000 cycles, at least about 500,000 cycles, or even atleast about 540,000 cycles. Still, the substrate may have a fatigue lifethat is not greater than about 2,000,000 cycles.

After providing a substrate at step 101, the process can continue atstep 102, which includes translating the substrate through a mixtureincluding abrasive particles and a particulate including a tackingmaterial. To facilitate processing and formation of the abrasivearticle, the substrate may be connected to a spooling mechanism. Forexample, the wire can be translated between a feed spool and a receivingspool. The translation of the wire between the feed spool and thereceiving spool can facilitate processing, such that for example, thewire may be translated through desired forming processes to form thecomponent layers of the finally-formed abrasive article while beingtranslated from the feed spool to the receiving spool.

In further reference to the process of providing a substrate, it will beappreciated that the substrate can be spooled from a feed spool to areceiving spool at a particular rate to facilitate processing. Forexample, the substrate can be spooled at a rate of not less than about 5m/min from the feed spool to the receiving spool. In other embodiments,the rate of spooling can be greater, such that it is at least about 8m/min, at least about 10 m/min, at least about 12 m/min, or even atleast about 14 m/min. In particular instances, the spooling rate may benot greater than about 500 m/min, such as not greater than about 200m/min. The rate of spooling can be within a range between any of theminimum and maximum values noted above. It will be appreciated thespooling rate can represent the rate at which the finally-formedabrasive article can be formed.

In certain instances, the substrate can include one or more optionalbarrier layers overlying the exterior surface of the substrate.According to one aspect, the barrier layer can be overlying the exteriorsurface of a substrate, such that it may be in direct contact with theexterior (i.e., peripheral) surface of the substrate, and moreparticularly, can be bonded directly to the exterior surface of thesubstrate. In one embodiment, the barrier layer can be bonded to theexterior surface of the substrate and may define a diffusion bond regionbetween the barrier layer and the substrate, characterized by aninterdiffusion of at least one metal element of the substrate and oneelement of the barrier layer. In one particular embodiment, the barrierlayer can be disposed between the substrate and other overlying layers,including for example, a tacking layer, a bonding layer, a coatinglayer, a layer of one or more types of abrasive particles, or acombination thereof.

The process of providing a substrate having a barrier layer can includesourcing such a construction or fabricating such a substrate and barrierlayer construction. The barrier layer can be formed through varioustechniques, including for example, a deposition process. Some suitabledeposition processes can include, printing, spraying, dip coating, diecoating, plating (e.g., electrolytic or electroless), and a combinationthereof. In accordance with an embodiment, the process of forming thebarrier layer can include a low temperature process. For example, theprocess of forming the barrier layer can be conducted at a temperatureof not greater than about 400° C., such as not greater than about 375°C., not greater than about 350° C., not greater than about 300° C., oreven not greater than about 250° C. Furthermore, after forming thebarrier layer it will be appreciated that further processing can beundertaken including for example cleaning, drying, curing, solidifying,heat treating, and a combination thereof. The barrier layer can serve asa barrier to chemical impregnation of the core material by variouschemical species (e.g., hydrogen) in subsequent plating processes.Moreover, the barrier layer may facilitate improved mechanicaldurability.

In one embodiment, the barrier layer can be a single layer of material.The barrier layer can be in the form of a continuous coating, overlyingthe entire peripheral surface of the substrate. The barrier material caninclude an inorganic material, such as a metal or metal alloy material.Some suitable materials for use in the barrier layer can includetransition metal elements, including but not limited to tin, silver,copper, zinc, nickel, titanium, and a combination thereof. In anotherembodiment, the barrier layer may include brass. In one embodiment, thebarrier layer can be a single layer of material consisting essentiallyof tin. In one particular instance, the barrier layer can contain acontinuous layer of tin having a purity of at least 99.99% tin. Notably,the barrier layer can be a substantially pure, non-alloyed material.That is, the barrier layer can be a metal material (e.g., tin) made of asingle metal material.

In other embodiments, the barrier layer can be a metal alloy. Forexample, the barrier layer can include a tin alloy, such as acomposition including a combination of tin and another metal, includingtransition metal species such as copper, silver, and the like. Somesuitable tin-based alloys can include tin-based alloys including silver,and particularly Sn96.5/Ag3.5, Sn96/Ag4, and Sn95/Ag5 alloys. Othersuitable tin-based alloys can include copper, and particularly includingSn99.3/Cu0.7 and Sn97/Cu3 alloys. Additionally, certain tin-based alloyscan include a percentage of copper and silver, including for example,Sn99/Cu0.7/Ag0.3, Sn97/Cu2.75/Ag0.25 and, Sn95.5/Ag4/Cu0.5 alloys. Instill another embodiment, the barrier layer can include a metal alloyincluding a combination of copper and nickel, and more specifically mayinclude a metal alloy consisting essentially of copper and nickel.

In another aspect, the barrier layer can be formed from a plurality ofdiscrete layers, including for example, at least two discrete layers.For example, the barrier layer can include an inner layer and an outerlayer overlying the inner layer. According to an embodiment, the innerlayer and outer layer can be directly contacting each other, such thatthe outer layer is directly overlying the inner layer and joined at aninterface. Accordingly, the inner layer and outer layer can be joined atan interface extending along the length of the substrate.

In one embodiment, the inner layer can include any of thecharacteristics of the barrier layer described above. For example, theinner layer can include a continuous layer of material including tin,copper, nickel, or a combination thereof. Moreover, the inner layer andouter layer can be formed of different materials relative to each other.That is, for example, at least one element present within one of thelayers can be absent within the other layer. In one particularembodiment, the outer layer can include an element that is not presentwithin the inner layer.

The outer layer can include any of the characteristics of the barrierlayer described above. For example, the outer layer can be formed suchthat it includes an inorganic material, such as a metal or a metalalloy. More particularly, the outer layer can include a transition metalelement. For example, in one certain embodiment, the outer layer caninclude nickel. In another embodiment, the outer layer can be formedsuch that it consists essentially of nickel.

In certain instances, the outer layer can be formed in the same manneras the inner layer, such as a deposition process. However, it is notnecessary that the outer layer be formed in the same manner as the innerlayer. In accordance with an embodiment, the outer layer can be formedthrough a deposition process including plating, spraying, printing,dipping, die coating, deposition, and a combination thereof. In certaininstances, the outer layer of the barrier layer can be formed atrelatively low temperatures, such as temperatures not greater than about400° C., not greater than about 375° C., not greater than about 350° C.,not greater than about 300° C., or even not greater than 250° C.According to one particular process, the outer layer can be formedthough a non-plating process, such as die coating. Moreover, theprocesses used to form the outer layer may include other methodsincluding for example heating, curing, drying, and a combinationthereof. It will be appreciated that formation of the outer layer insuch a manner may facilitate limiting the impregnation of unwantedspecies within the core and/or inner layer.

In accordance with an embodiment, the inner layer of the barrier layercan be formed to have a particular average thickness suitable for actingas a chemical barrier layer. For example, the barrier layer can have anaverage thickness of at least about 0.05 microns, such as least about0.1 microns, at least about 0.2 microns, at least about 0.3 micron, oreven at least about 0.5 microns. Still, the average thickness of theinner layer may be not greater than about 8 microns, such as not greaterthan about 7 microns, not greater than about 6 microns, not greater thanabout 5 microns, or even not greater than about 4 microns. It will beappreciated that the inner layer can have an average thickness within arange between any of the minimum and maximum thicknesses noted above.

The outer layer of the barrier layer can be formed to have a particularthickness. For example, in one embodiment the average thickness of theouter layer can be at least about 0.05 microns, such as least about 0.1microns, at least about 0.2 microns, at least about 0.3 micron, or evenat least about 0.5 microns. Still, in certain embodiments, the outerlayer can have an average thickness that is not greater than about 12microns, not greater than about 10 microns, not greater than about 8microns, not greater than about 7 microns, not greater than about 6microns, not greater than about 5 microns, not greater than about 4microns, or even not greater than about 3 microns. It will beappreciated that the outer layer of the barrier layer can have anaverage thickness within a range between any of the minimum and maximumthicknesses noted above.

Notably, in at least one embodiment, the inner layer can be formed tohave a different average thickness than the average thickness of theouter layer. Such a design may facilitate improved impregnationresistance to certain chemical species while also providing suitablebonding structure for further processing. For example, in otherembodiments the inner layer can be formed to have an average thicknessthat is greater than the average thickness of the outer layer. However,in alternative embodiments, the inner layer may be formed to have anaverage thickness so that it is less than the average thickness of theouter layer.

According to one particular embodiment, the barrier layer can have athickness ratio [t_(i):t_(o)] between an average thickness of the innerlayer (t_(i)) and an average thickness of the outer layer (t_(o)) thatcan be within a range between about 3:1 and about 1:3. In otherembodiments, the thickness ratio can be within a range between about2.5:1 and about 1:2.5, such as within a range between about 2:1 andabout 1:2, within a range between about 1.8:1 and about 1:1.8, within arange between about 1.5:1 and about 1:1.5, or even within a rangebetween about 1.3:1 and about 1:1.3.

Notably, the barrier layer (including at least the inner layer and outerlayer) can be formed to have an average thickness that is not greaterthan about 10 microns. In other embodiments, the average thickness ofthe barrier layer may be less, such as not greater than about 9 microns,not greater than about 8 microns, not greater than about 7 microns, notgreater than about 6 microns, not greater than about 5 microns, or evennot greater than about 3 microns. Still, the average thickness of thebarrier layer can be at least about 0.05 microns, such as least about0.1 microns, at least about 0.2 microns, at least about 0.3 micron, oreven at least about 0.5 microns. It will be appreciated that the barrierlayer can have an average thickness within a range between any of theminimum and maximum thicknesses noted above.

Still, in another embodiment, the substrate may not necessarily includea barrier layer or any coatings on the exterior surface. For example,the substrate may be essentially free of a barrier layer. , wherein thesubstrate is essentially free of a barrier layer. In at least oneembodiment, the substrate can be an uncoated wire prior to translatingthe substrate through a mixture, which will be described herein at step102. More particularly, the substrate can be a metal wire that isessentially free of any coating layers on an exterior surface prior tothe process of translating the wire through a mixture as described instep 102.

After providing the substrate, the process can continue at step 102,which includes translating the substrate through a mixture includingabrasive particles and a particulate material including a tackingmaterial. FIG. 2A includes an illustration of a process for forming anabrasive article in accordance with an embodiment. FIG. 2B includes anillustration of a portion of the process of forming an abrasive articlein accordance with an embodiment. As illustrated, the substrate 201 canbe translated in a direction 202 into a container 203 including amixture 204. The substrate 201 may be translated over one or morerollers 205 within the container to facilitate control of the directionof the substrate 201 and proper processing.

According to one particular embodiment, the process of forming a portionof the abrasive article can include a slurry dip-coating process,wherein the substrate 201 is translated through a mixture 204 includingabrasive particles 212 and a particulate 213 including a tackingmaterial that can facilitate formation of an abrasive article having thefeatures of the embodiments herein. Notably, the mixture 204 can includethe abrasive particles 212 and particulate 213, which may facilitate theformation of discrete tacking regions and discrete formations in thefinally-formed abrasive article. Moreover, as illustrated and describedherein, unlike certain other conventional approaches, the mixture 204can include the particulate 213 and abrasive particles 212, and thusfacilitate simultaneous attachment of both the abrasive particles 212and particulate 213 to the substrate 201.

Reference herein to abrasive particles is reference to any one of themultiple types of abrasive particle described herein, including forexample a first type of abrasive particle or a second type of abrasiveparticle. The abrasive particles can include a material such as anoxide, a carbide, a nitride, a boride, an oxynitride, an oxyboride,diamond, and a combination thereof. In certain embodiments, the abrasiveparticles can incorporate a superabrasive material. For example, onesuitable superabrasive material includes diamond. In particularinstances, the abrasive particles can consist essentially of diamond. Asnoted herein, the mixture can include more than one type of abrasiveparticle, including for example, a first type of abrasive particle and asecond type of abrasive particle. The first and second types of abrasiveparticles may have at least one abrasive characteristic that isdifferent compared to each other, wherein the abrasive characteristiccan include composition, average particle size, hardness, toughness,friability, structure, shape, or a combination thereof. Moreover, incertain instances, wherein the mixture includes more than one type ofabrasive particle, the content of the different types of abrasiveparticles can be different within the mixture, and therefore, differentin the finally-formed abrasive article.

In one embodiment, the abrasive particles can include a material havinga Vickers hardness of at least about 10 GPa. In other instances, theabrasive particles can have a Vickers hardness of at least about 25 GPa,such as at least about 30 GPa, at least about 40 GPa, at least about 50GPa, or even at least about 75 GPa. Still, in at least one non-limitingembodiment, the abrasive particles can have a Vickers hardness that isnot greater than about 200 GPa, such as not greater than about 150 GPa,or even not greater than about 100 GPa. It will be appreciated that theabrasive particles can have a Vickers hardness within a range betweenany of the minimum and maximum values noted above.

The abrasive particles can have a particular shape, such as a shape fromthe group including elongated, equiaxed, ellipsoidal, boxy, rectangular,triangular, irregular, and the like. Moreover, in certain instances, theabrasive particles can have a particular crystalline structure,including but not limited to multicrystalline, monocrystalline,polygonal, cubic, hexagonal, tetrahedral, octagonal, complex carbonstructure (e.g., Bucky-ball), and a combination thereof.

Moreover, the abrasive particles may have a particular grit sizedistribution that may facilitate improved manufacturing and/orperformance of the abrasive article. For example, the abrasive particlescan be present in the mixture and on the abrasive article in a normal orGaussian distribution. In still, other instances, the abrasive particlescan be present in the mixture in a non-Gaussian distribution, includingfor example, a multi-modal distribution or a wide grit sizedistribution. For a wide grit size distribution, at least 80% of theabrasive particles can have an average particle size contained within arange of at least about 30 microns over a range of average particlesizes between about 1 micron to about 100 microns. In one embodiment,the wide grit size distribution can be a bimodal particle sizedistribution, wherein the bimodal particle size distribution comprises afirst mode defining a first median particle size (M1) and a second modedefining a second median particle size (M2) that is different than thefirst median particle size. According to a particular embodiment, thefirst median particle size and second median particle size are at least5% different based on the equation ((M1−M2)/M1)×100%. In still otherembodiments, the first median particle size and the second medianparticle size can be at least about 10% different, such as at leastabout 20% different, at least about 30% different, at least about 40%different, at least about 50% different, at least about 60% different,at least about 70% different, at least about 80% different, or even atleast about 90% different. Yet, in another non-limiting embodiment, thefirst median particle size may be not greater than about 99% different,such as not greater than about 90% different, not greater than about 80%different, not greater than about 70% different, not greater than about60% different, not greater than about 50% different, not greater thanabout 40% different, not greater than about 30% different, not greaterthan about 20% different, or even not greater than about 10% differentthan the second median particle size. It will be appreciated that thedifference between the first median particle size and the second medianparticle size can be within a range between any of the above minimum andmaximum percentages.

For a particular embodiment, the abrasive particles can include anagglomerated particle. More particularly, the abrasive particles canconsist essentially of agglomerated particles. In certain instances, themixture may include a combination of agglomerated abrasive particles andunagglomerated abrasive particles. According to an embodiment, anagglomerated particle can include abrasive particles bonded to eachother by a binder material. Some suitable examples of a binder materialcan include an inorganic material, an organic material, and acombination thereof. More particularly, the binder material may be aceramic, a metal, a glass, a polymer, a resin, and a combinationthereof. In at least one embodiment, the binder material can be a metalor metal alloy, which may include one or more transition metal elements.According to an embodiment, the binder material can include at least onemetal element from a component layer of the abrasive article, includingfor example, the barrier layer, the tacking material, the bonding layer,or a combination thereof. In a more particular embodiment, the bindercan be a metal material that includes at least one active binding agent.The active binding agent may be an element or composition including anitride, a carbide, and combination thereof. One particular exemplaryactive binding agent can include a titanium-containing composition, achromium-containing composition, a nickel-containing composition, acopper-containing composition and a combination thereof. In anotherembodiment, the binder material can include a chemical agent configuredto chemically react with a workpiece in contact with the abrasivearticle to facilitate a chemical removal process on the surface of theworkpiece while the abrasive article is also conducting a mechanicalremoval process. Some suitable chemical agents can include oxides,carbides, nitrides, an oxidizer, pH modifier, surfactant, and acombination thereof.

The agglomerated particle of embodiments herein can include a particularcontent of abrasive particles, a particular content of binder material,and a particular content of porosity. For example, the agglomeratedparticle can include a greater content of abrasive particle than acontent of binder material. Alternatively, the agglomerated particle caninclude a greater content of binder material than a content of abrasiveparticle. For example, in one embodiment, the agglomerated particle caninclude at least about 5 vol % abrasive particle for the total volume ofthe agglomerated particle. In other instances, the content of abrasiveparticles for the total volume of the agglomerated particle can begreater, such as at least about 10 vol %, such as at least about 20 vol%, at least about 30 vol %, at least about 40 vol %, at least about 50vol %, at least about 60 vol %, at least about 70 vol %, at least about80 vol %, or even at least about 90 vol %. Yet, in another non-limitingembodiment, the content of abrasive particles in an agglomeratedparticle for the total volume of the agglomerated particle can be notgreater than about 95 vol %, such as not greater than about 90 vol %,not greater than about 80 vol %, not greater than about 70 vol %, notgreater than about 60 vol %, not greater than about 50 vol %, notgreater than about 40 vol %, not greater than about 30 vol %, notgreater than about 20 vol %, or even not greater than about 10 vol %. Itwill be appreciated that the content of the abrasive particles in theagglomerated particle can be within a range between any of the aboveminimum and maximum percentages.

According to another aspect, the agglomerated particle can include atleast about 5 vol % binder material for the total volume of theagglomerated particle. In other instances, the content of bindermaterial for the total volume of the agglomerated particle can begreater, such as at least about 10 vol %, such as at least about 20 vol%, at least about 30 vol %, at least about 40 vol %, at least about 50vol %, at least about 60 vol %, at least about 70 vol %, at least about80 vol %, or even at least about 90 vol %. Yet, in another non-limitingembodiment, the content of binder material in an agglomerated particlefor the total volume of the agglomerated particle can be not greaterthan about 95 vol %, such as not greater than about 90 vol %, notgreater than about 80 vol %, not greater than about 70 vol %, notgreater than about 60 vol %, not greater than about 50 vol %, notgreater than about 40 vol %, not greater than about 30 vol %, notgreater than about 20 vol %, or even not greater than about 10 vol %. Itwill be appreciated that the content of the binder material in theagglomerated particle can be within a range between any of the aboveminimum and maximum percentages.

In yet another aspect, the agglomerated particle can include aparticular content of porosity. For example, the agglomerated particlecan include at least about 1 vol % porosity for the total volume of theagglomerated particle. In other instances, the content of porosity forthe total volume of the agglomerated particle can be greater, such as atleast about 5 vol %, at least about 10 vol %, at least about 20 vol %,at least about 30 vol %, at least about 40 vol %, at least about 50 vol%, at least about 60 vol %, at least about 70 vol %, or even at leastabout 80 vol %. Yet, in another non-limiting embodiment, the content ofporosity in an agglomerated particle for the total volume of theagglomerated particle can be not greater than about 90 vol %, notgreater than about 80 vol %, not greater than about 70 vol %, notgreater than about 60 vol %, not greater than about 50 vol %, notgreater than about 40 vol %, not greater than about 30 vol %, notgreater than about 20 vol %, or even not greater than about 10 vol %. Itwill be appreciated that the content of the porosity in the agglomeratedparticle can be within a range between any of the above minimum andmaximum percentages.

The porosity within the agglomerated particle can be of various types.For example, the porosity can be closed porosity, generally defined bydiscrete pores that are spaced apart from each other within the volumeof the agglomerated particle. In at least one embodiment, a majority ofthe porosity within the agglomerated particle can be closed porosity.Alternatively, the porosity can be open porosity, defining a network ofinterconnected channels extending through the volume of the agglomeratedparticle. In certain instances, a majority of the porosity can be openporosity.

The agglomerated particle can be sourced from a supplier. Alternatively,the agglomerated particle may be formed prior to the formation of theabrasive article. Suitable processes for forming the agglomeratedparticle can include screening, mixing, drying, solidifying, electrolessplating, electrolyte plating, sintering, brazing, spraying, printing,and a combination thereof.

According to one particular embodiment, the agglomerated particle can beformed in-situ with the formation of the abrasive article. For example,the agglomerated particle may be formed while forming one or morecomponent layers of the abrasive article. Suitable processes for formingthe agglomerated particle in-situ with the abrasive article can includea deposition process. Particular deposition processes can include, butare not limited to, plating, electroplating, dipping, spraying,printing, coating, gravity coating, and a combination thereof. In atleast one particular embodiment, the process of forming the agglomeratedparticle comprises simultaneously forming a bonding layer and theagglomerated particle via a plating process.

According to at least one embodiment, the abrasive particles can have aparticle coating layer. Notably, the particle coating layer can overliethe exterior surface of the abrasive particles, and more particularly,may be in direct contact with the exterior surface of the abrasiveparticles. Suitable materials for use as the particle coating layer caninclude a metal or metal alloy. In accordance with one particularembodiment, the particle coating layer can include a transition metalelement, such as titanium, vanadium, chromium, molybdenum, iron, cobalt,nickel, copper, silver, zinc, manganese, tantalum, tungsten, and acombination thereof. One certain particle coating layer can includenickel, such as a nickel alloy, and even alloys having a majoritycontent of nickel, as measured in weight percent as compared to otherspecies present within the first particle coating layer. In moreparticular instances, the particle coating layer can include a singlemetal species. For example, the first particle coating layer can consistessentially of nickel. The particle coating layer can be a plated layer,such that it may be an electrolyte plated layer and an electrolessplated layer.

The particle coating layer can be formed to overlie at least a portionof the exterior surface of the abrasive particles. For example, theparticle coating layer may overly at least about 50% of the exteriorsurface area of the abrasive particles. In other embodiments, thecoverage of the particle coating layer can be greater, such as at leastabout 75%, at least about 80%, at least about 90%, at least about 95%,or essentially the entire exterior surface of the abrasive particles.

The particle coating layer may be formed to have a particular contentrelative to the amount of the first type of abrasive particle tofacilitate processing. For example, the particle coating layer can be atleast about 5% of the total weight of each of the abrasive particles. Inother instances, the relative content of the particle coating layer tothe total weight of each of the abrasive particles can be greater, suchas at least about 10%, at least about 20%, at least about 30%, at leastabout 40%, at least about 50%, at least about 60%, at least about 70%,or even at least about 80%. Yet, in another non-limiting embodiment, therelative content of the particle coating layer to the total weight ofthe abrasive particles may be not greater than about 99%, such as notgreater than about 90%, not greater than about 80%, not greater thanabout 70%, not greater than about 60%, not greater than about 50%, notgreater than about 40%, not greater than about 30%, not greater thanabout 20%, or even not greater than about 10%. It will be appreciatedthat the relative content of the particle coating layer to the totalweight of the abrasive particles can be within a range between any ofthe minimum and maximum percentages noted above.

According to one embodiment, the particle coating layer can be formed tohave a particular thickness suitable to facilitate processing. Forexample, the particle coating layer can have an average thickness of notgreater than about 5 microns, such as not greater than about 4 microns,not greater than about 3 microns, or even not greater than about 2microns. Still, according to one non-limiting embodiment, the particlecoating layer can have an average thickness of at least about 0.01microns, 0.05 microns, at least about 0.1 microns, or even at leastabout 0.2 microns. It will be appreciated that the average thickness ofthe particle coating layer can be within a range between any of theminimum and maximum values noted above.

According to certain aspects herein, the particle coating layer can beformed of a plurality of discrete film layers. For example, the particlecoating layer can include a first particle film layer overlying theabrasive particles, and a second particle film layer different than thefirst particle film layer overlying the first particle film layer. Thefirst particle film layer may be in direct contact with an exteriorsurface of the abrasive particles and the second particle film layer maybe in direct contact with the first particle film layer. The firstparticle film layer and second particle film layer can be distinct fromeach other based on at least one material parameter such as averagethickness, composition, melting temperature, or a combination thereof.

According to at least one embodiment, the abrasive particles may have aparticular size that facilitates improved manufacturing and/orperformance of the abrasive article. For example, the abrasive particles212 can have an average particle size (PSa) of not greater than 500microns, such as not greater than 300 microns, not greater than 200microns, not greater than 150 microns, not greater than 100 microns, notgreater than 80 microns, not greater than 70 microns, not greater than60 microns, not greater than 50 microns, not greater than 40 microns,not greater than 30 microns or even not greater than 20 microns. Yet, ina non-limiting embodiment, the abrasive particles 212 may have anaverage particle size (PSa) of at least about 0.1 microns, such as atleast about 0.5 microns, at least about 1 micron, at least about 2microns, at least about 5 microns, or even at least about 8 microns. Itwill be appreciated that the average particle size can be within a rangebetween any of the above minimum and maximum percentages, including forexample, at least 1 micron and not greater than 100 microns or at least2 microns and not greater than 80 microns.

The mixture 204 can include a particular content of abrasive particles212, which may facilitate improved manufacturing and/or performance ofthe abrasive article. For example, the mixture 204 may include at least5 wt % abrasive particles for a total weight of the mixture. Still, inother instances, the content of the abrasive particles 212 in themixture 204 can be greater, such as at least 8 wt % or at least 10 wt %or at least 12 wt % or at least 14 wt % or at least 16 wt % or at least18 wt % or at least 20 wt % or at least 22 wt % or at least 24 wt % orat least 26 wt % or at least 28 wt % or at least 30 wt % or at least 32wt % or at least 34 wt % or at least 36 wt % or at least 38 wt % or atleast 40 wt % or at least 42 wt % or at least 44 wt % or at least 46 wt% or at least 48 wt % or at least 50 wt % for a total weight of themixture. Still, in at least one non-limiting embodiment, the content ofabrasive particles 212 in the mixture 204 can be not greater than 80 wt%, such as not greater than 75 wt % or not greater than 70 wt % or notgreater than 65 wt % or not greater than 60 wt % or not greater than 55wt % or not greater than 50 wt % or not greater than 45 wt % or notgreater than 40 wt % or not greater than 30 wt % or not greater than 25wt % or not greater than 20 wt % for a total weight of the mixture. Itwill be appreciated that the mixture 204 can include a content of theabrasive particles 212 within a range including any of the minimum andmaximum percentages noted above. Furthermore, the content of theabrasive particles 212 in the mixture 204 can be controlled and modifieddepending upon the size (e.g., width or diameter) of the substrate, theaverage particle size of the abrasive particles, and the desiredconcentration of abrasive particles present on the substrate in thefinally-formed abrasive article.

As described herein, mixture 204 may further include a particulate 213,which can include a tacking material. The particulate 213 may be apowder material, such as a raw material powder suitable for formingdiscrete tacking regions and discrete formations as described inembodiments herein. The particulate 213 may consist essentially of atacking material. The particulate 213 may facilitate provisional bondingof the abrasive particles 212 to the substrate 201 until furtherprocessing, which can include the application of a bonding layer, can becompleted to permanently secure the abrasive particles to the substrate201.

In accordance with an embodiment, the tacking material can be formedfrom a metal, metal alloy, metal matrix composite, and a combinationthereof. In one particular embodiment, the tacking material can beformed of a material including a transition metal element. For example,the tacking material can be a metal alloy including a transition metalelement. Some suitable transition metal elements can include, lead,silver, copper, zinc, indium, tin, titanium, molybdenum, chromium, iron,manganese, cobalt, niobium, tantalum, tungsten, palladium, platinum,gold, ruthenium, and a combination thereof. According to one particularembodiment, the tacking material can be made of a metal alloy includingtin and lead. In particular, such metal alloys of tin and lead maycontain a majority content of tin as compared to lead, including but notlimited to, a tin/lead composition of at least about 60/40.

In another embodiment, the tacking material can be made of a materialhaving a majority content of tin. In fact, in certain abrasive articles,the tacking material may consist essentially of tin. The tin, alone orin the solder, can have a purity of at least about 99%, such as at leastabout 99.1%, at least about 99.2%, at least about 99.3%, at least about99.4%, at least about 99.5%, at least about 99.6%, at least about 99.7%,at least about 99.8%, or even at least about 99.9%. In another aspect,the tin can have a purity of at least about 99.99%. In one particularinstance, the tacking material can include a matte tin material. Thetacking material may have an organic content of not greater than about0.5 wt % for a total weight of the plated material (i.e., the tackinglayer).

In accordance with an embodiment, the tacking material can be a soldermaterial. It will be appreciated that a solder material may include amaterial having a particular melting point, such as not greater thanabout 450° C. Solder materials are distinct from braze materials, whichgenerally have significantly higher melting points than soldermaterials, such as greater than 450° C., and more typically, greaterthan 500° C. Furthermore, brazing materials may have differentcompositions. In accordance with an embodiment, the tacking material ofthe embodiments herein may be formed of a material having a meltingpoint of not greater than about 400° C., such as not greater than about375° C., not greater than about 350° C., not greater than about 300° C.,or even not greater than about 250° C. Still, the tacking material mayhave a melting point of at least about 100° C., such as at least about125° C., at least about 150° C., or even at least about 175° C. It willbe appreciated that the tacking material can have a melting point withina range between any of the minimum and maximum temperatures noted above.

According to one embodiment, the tacking material can include a samematerial as the barrier layer, such that the compositions of the barrierlayer and the tacking material share at least one element in common. Inyet an alternative embodiment, the barrier layer and the tackingmaterial can be entirely different materials.

According to at least one embodiment, the particulate including thetacking material may have a certain particle size that facilitatesimproved manufacturing and/or performance of the abrasive article. Forexample, the particulate 213 can have an average particle size (PSp) ofnot greater than 50 microns, such as not greater than 40 microns, notgreater than 30 microns, not greater than 25 microns, not greater than20 microns, not greater than 18 microns, not greater than 15 microns,not greater than 12 microns, not greater than 10 microns, not greaterthan 8 microns, not greater than 5 microns or even not greater than 3microns. Yet, in a non-limiting embodiment, the particulate 213 may havean average particle size (PSp) of at least about 0.01 microns, such asat least about 0.05 microns, at least about 0.1 microns, at least about0.22 microns, at least about 0.5 microns, or even at least about 1micron. It will be appreciated that the average particle size can bewithin a range between any of the above minimum and maximum percentages,including for example, at least 0.01 micron and not greater than 50microns, at least 0.1 microns and not greater than 10 microns or even atleast 0.5 microns and not greater than 7 microns.

The mixture 204 can include a particular content of the particulate 213including the tacking material, which may facilitate improvedmanufacturing and/or performance of the abrasive article. For example,the mixture 204 may include at least 0.1 wt % particulate for a totalweight of the mixture. Still, in other instances, the content of theparticulate 213 in the mixture 204 can be greater, such as at least 0.2wt % or at least 0.3 wt % or at least 0.4 wt % or at least 0.5 wt % orat least 0.8 wt % or at least 1 wt % or at least 1.2 wt % or at least1.5 wt % or at least 1.8 wt % or at least 2 wt % or at least 2.2 wt % orat least 2.5 wt % or at least 2.8 wt % or at least 3 wt % or at least 4wt % or at least 5 wt % or at least 6 wt % or at least 7 wt % or atleast 8 wt % or at least 9 wt % or at least 10 wt % for a total weightof the mixture. Still, in at least one non-limiting embodiment, thecontent of the particulate 213 including the tacking material in themixture 204 can be not greater than 25 wt %, such as not greater than 22wt % or not greater than 20 wt % or not greater than 18 wt % or notgreater than 15 wt % or not greater than 12 wt % or not greater than 10wt % or not greater than 9 wt % or not greater than 8 wt % or notgreater than 7 wt % or not greater than 6 wt % or not greater than 5 wt% or not greater than 4 wt % or not greater than 3 wt % for a totalweight of the mixture. It will be appreciated that the mixture 204 caninclude a content of the particulate 213 including the tacking materialwithin a range including any of the minimum and maximum percentagesnoted above, including for example, at least 0.2 wt % and not greaterthan 20 wt % or even at least 0.5 wt % and not greater than 10 wt %.Furthermore, the content of the particulate in the mixture 204 can becontrolled and modified depending upon the size (e.g., width ordiameter) of the substrate, the average particle size of the abrasiveparticles, and the desired concentration of abrasive particles presenton the substrate in the finally-formed abrasive article.

According to another embodiment, the mixture 204 can include abrasiveparticles 212 and particulate 213 having a certain relationship in theirrespective average particles sizes which can facilitate improvedmanufacturing and/or performance of the abrasive article. For example,the mixture 204 can include abrasive particles 212 having an averageparticle size (PSa) and the particulate having an average particles size(PSp), wherein the mixture 204 can be formed to have a ratio (PSp/PSa)of not greater than 1. In other instances, the ratio (PSp/PSa) can beless, such as not greater than 0.9 or not greater than 0.8 or notgreater than 0.7 or not greater than 0.6 or not greater than 0.5 or notgreater than 0.4 or not greater than 0.3 or not greater than 0.2 or notgreater than 0.18 or not greater than 0.16 or not greater than 0.15 ornot greater than 0.014 or not greater than 0.13 or no greater than 0.12or not greater than 0.11 or not greater than 0.1 or not greater than0.09 or not greater than 0.08 or not greater than 0.07 or not greaterthan 0.06 or no greater than 0.05 or not greater than 0.04 or notgreater than 0.03 or not greater than 0.02. Still, in at least onenon-limiting embodiment, the mixture 204 can be formed to have a ratio(PSp/PSa) of at least 0.01, such as at least 0.02 or at least 0.03 or atleast 0.04 or at least 0.05 or at least 0.06 or at least 0.07 or atleast 0.08 or at least 0.09 or at least 0.1 or at least 0.11 or at least0.12 or at least 0.13 or at least 0.14 or at least 0.15 or at least 0.16or at least 0.17 or at least 0.18 or at least 0.19 or at least 0.2 or atleast 0.3 or at least 0.4 or at least 0.5 or at least 0.6 or at least0.7 or at least 0.8 or at least 0.9. It will be appreciated that themixture 204 can have a ratio (PSp/PSa) within a range including any ofthe minimum and maximum values noted above, including for example, atleast 0.01 and not greater than 1, at least 0.01 and not greater than0.5 or even at least about 0.025 and not greater than about 0.25.Furthermore, the ratio (PSp/PSa) may be controlled and modifieddepending upon the size (e.g., width or diameter) of the substrate andthe desired concentration of abrasive particles present on the substratein the finally-formed abrasive article.

According to another embodiment, the mixture 204 can include abrasiveparticles 212 and particulate 213 having a certain relationship in theirrespective contents within the mixture, as measured in weight percent,which can facilitate improved manufacturing and/or performance of theabrasive article. For example, the mixture 204 a content of abrasiveparticles (Cap) and a content of the particulate (Cp) wherein themixture 204 can be formed to have a ratio (Cp/Cap) of not greater than10. In other instances, the ratio (Cp/Cap) can be less, such as notgreater than 5 or not greater than 3 or not greater than 2 or notgreater than 1 or not greater than 0.9 or not greater than 0.8 or notgreater than 0.7 or not greater than 0.6 or not greater than 0.5 or notgreater than 0.4 or not greater than 0.3 or not greater than 0.2 or notgreater than 0.18 or not greater than 0.16 or not greater than 0.15 ornot greater than 0.014 or not greater than 0.13 or no greater than 0.12or not greater than 0.11 or not greater than 0.1 or not greater than0.09 or not greater than 0.08 or not greater than 0.07 or not greaterthan 0.06 or no greater than 0.05 or not greater than 0.04 or notgreater than 0.03 or not greater than 0.02. Still, in at least onenon-limiting embodiment, the mixture 204 can be formed to have a ratio(Cp/Cap) of at least 0.001 or at least 0.0025 or at least 0.004 or atleast 0.006 or at least 0.008 or at least 0.01 or at least 0.02 or atleast 0.03 or at least 0.04 or at least 0.05 or at least 0.06 or atleast 0.07 or at least 0.08 or at least 0.09 or at least 0.1 or at least0.11 or at least 0.12 or at least 0.13 or at least 0.14 or at least 0.15or at least 0.16 or at least 0.17 or at least 0.18 or at least 0.19 orat least 0.2 or at least 0.3 or at least 0.4 or at least 0.5 or at least0.6 or at least 0.7 or at least 0.8 or at least 0.9. It will beappreciated that the mixture 204 can have a ratio (Cp/Cap) within arange including any of the minimum and maximum values noted above,including for example, at least 0.001 and not greater than 1, even atleast 0.01 and not greater than 0.5 or even at least 0.025 and notgreater than 0.25. Furthermore, the ratio (Cp/Cap) may be controlled andmodified depending upon the size (e.g., width or diameter) of thesubstrate and the desired concentration of abrasive particles present onthe substrate in the finally-formed abrasive article.

According to another embodiment, the mixture 204 can include a carrierfor suspending the abrasive particles 212, particulate 213 and anyadditives therein. According to one embodiment, the carrier can includewater, such that the mixture is an aqueous-based slurry.

In another embodiment, the mixture 204 may include certain additives.For example, the mixture 204 can include a flux material 211, which maybe applied to the substrate 201 as it is translated through the mixture204. According to one particular embodiment, during processing, the fluxmaterial 211 may form a generally continuous and conformal coating onthe substrate 201 as it is translated and exits the mixture 204, whichcan facilitate suitable coupling of the abrasive particles 212 andparticulate 213 to the substrate 201. The flux material 211 can be inthe form of a liquid or paste. For at least one exemplary embodiment,the flux material 211 can include a material such as a chloride, anacid, a surfactant, a solvent, organics, water and a combinationthereof. In one particular embodiment, the flux material 211 can includehydrochloride, zinc chloride, and a combination thereof.

As illustrated in FIGS. 2A and 2B, the process can be conducted suchthat at least a portion of the abrasive particles 212, particulate 213and flux 211 from the mixture are attached to the substrate 201.Notably, as the substrate 201 exits the mixture 204, a layer of materialincluding a flux material 211, abrasive particles 212, and theparticulate 213 including the tacking material can be simultaneouslyattached to the substrate 201. It will be appreciated that the rheologyof the mixture 204 and the rate of translation of the substrate 201 maybe controlled to facilitate suitable application of the flux material211, abrasive particles 212 and particulate 213 to the substrate 201.Notably, the process of attaching the flux material 211, abrasiveparticles 212 and particulate 213 to the substrate 201 can be conductedat a temperature within a range including at least 1° C. and not greaterthan 300° C. Notably, this temperature range may ensure that theparticulate material is in a solid phase, as opposed to a liquid (e.g.,molten or melted) phase, which can facilitate the formation of anabrasive article having the features of the embodiments herein. Notably,the particulate 213 in the mixture 204 can be in a solid form and in asolid form when initially attached to the substrate 201. Laterprocessing may change the phase of the particulate 213 from a solidphase to a liquid phase, such as during the processing of treating.

The mixture 204 may be formed to have certain characteristics thatfacilitate the forming process, including for example, a viscosity.According to an embodiment, the mixture 204 may be a Newtonian fluidhaving a viscosity of at least 0.1 mPa s and no more than 1 Pa s at atemperature of 25° C. and a shear rate of 1 1/s. The mixture 204 canalso be a non-Newtonian fluid having a viscosity of at least 1 mPa s andno more than 100 Pa s, or even not greater than about 10 Pa s, at theshear rate of 10 1/s as measured at a temperature of 25° C. Viscositycan be measured using a TA Instruments AR-G2 rotational rheometer using25 mm parallel plates, a gap of approximately 2 mm, shear rates of 0.1to 10 1/s at a temperature of 25° C. One or more viscosity modifiers maybe added as an additive to the mixture 204. For example, the mixture 204may include a minor content of additives, of which may include aviscosity modifier. Some suitable viscosity modifiers can includeorganic materials, such as glycerin, ethylene glycol, propylene glycol,and the like.

After translating the substrate 201 through the mixture 204 at step 102,the process can continue by treating the substrate to form an abrasivearticle preform at step 103. According to one embodiment, treatingincludes heating the preform to a temperature within a range includingat least 100° C. and not greater than 450° C. The treating process mayfacilitate melting of at least a portion of the particulate 213 to afluid or semi-fluid state, such that at least a portion of theparticulate 213 contacts at least a portion of the abrasive particlesand provisionally bonds the abrasive particles 212 to the surface of thesubstrate 212. Moreover, the treating process may also facilitateaccumulation of certain portions of only the particulate material on thesurface of the substrate 201, such that certain discrete formations maybe formed. Treating may include translating the substrate 201 through aheater 206 to facilitate heating and formation of the abrasive articlepreform having abrasive particles 212 provisionally bonded to thesurface of the substrate 201 at discrete tacking regions and also theformation of discrete formations as will be described herein. As willalso be appreciated in light of the disclosure, the process of attachingabrasive particles 212, particulate 213, and flux material 211 to thesurface of the substrate 201 and treating the article may facilitateformation of a discontinuous coating of tacking material on the surfaceof the substrate 201.

After treating, the abrasive article preform may be cleaned to removeexcess flux and other unwanted materials in preparation for furtherprocessing. According to one embodiment, the cleaning process mayutilize one or a combination of water, acids, bases, surfactants,catalysts, solvents, and a combination thereof. In one particularembodiment, the cleaning process can be a staged process, starting witha rinse of the abrasive article using a generally neutral material, suchas water or deionized water. The water may be room temperature or hot,having a temperature of at least about 40° C. After the rinsingoperation the cleaning process may include an alkaline treatment,wherein the abrasive article is traversed through a bath having aparticular alkalinity, which may include an alkaline material. Thealkaline treatment may be conducted at room temperature, oralternatively, at elevated temperatures. For example, the bath of thealkaline treatment may have a temperature of at least about 40° C., suchat least about 50° C., or even at least about 70° C., and not greaterthan about 200° C. The abrasive article may be rinsed after the alkalinetreatment.

After the alkaline treatment, the abrasive article may undergo anactivation treatment. The activation treatment may include traversingthe abrasive article through a bath having a particular element orcompound, including an acid, a catalyst, a solvent, a surfactant, and acombination thereof. In one particular embodiment, the activationtreatment can include an acid, such as a strong acid, and moreparticularly hydrochloric acid, sulfuric acid, and a combinationthereof. In some instances, the activation treatment can include acatalyst that may include a halide or halide-containing material. Somesuitable examples of catalysts can include potassium hydrogen fluoride,ammonium bifluoride, sodium bifluoride, and the like.

The activation treatment may be conducted at room temperature, oralternatively, at elevated temperatures. For example, the bath of theactivation treatment may have a temperature of at least about 40° C.,but not greater than about 200° C. The abrasive article may be rinsedafter the activation treatment.

According to one embodiment, after suitably cleaning the abrasivearticle, an optional process may be utilized to facilitate the formationof abrasive particles having exposed surfaces after complete formationof the abrasive article. For example, in one embodiment, an optionalprocess of selectively removing at least a portion of the particlecoating layer on the abrasive particles may be utilized. The selectiveremoval process may be conducted such that the material of the particlecoating layer is removed while other materials of the abrasive article,including for example, the tacking layer are less affected, or evenessentially unaffected. According to a particular embodiment, theprocess of selectively removing comprises etching. Some suitable etchingprocesses can include wet etching, dry etching, and a combinationthereof. In certain instances, a particular etchant may be used that isconfigured to selectively remove the material of the particle coatinglayer of the abrasive particles and leaving the tacking layer intact.Some suitable etchants can include nitric acid, sulfuric acid,hydrochloride acid, organic acid, nitric salt, sulfuric salt, chloridesalt, alkaline cyanide based solutions, and a combination thereof.

After treating at step 103, the process may continue with the formationof a bonding layer on the abrasive article preform at step 104.Formation of the bonding layer can facilitate formation of an abrasivearticle having improved performance, including but not limited to, wearresistance and particle retention. In accordance with an embodiment, thebonding layer can be bonded directly to the abrasive particles, portionsof the tacking material, and portions of the substrate.

Forming the bonding layer can include a deposition process. Somesuitable deposition processes can include plating (electrolyte orelectroless), spraying, dipping, printing, coating, and a combinationthereof. In accordance with one particular embodiment, the bonding layercan be formed by a plating process. For at least one particularembodiment, the plating process can be an electrolyte plating process.In another embodiment, the plating process can include an electrolessplating process.

The bonding layer can overlie a majority of an external surface of thesubstrate and an external surface of the abrasive particles. Moreover,in certain instances, the bonding layer can overlie a majority of anexternal surface of the substrate and an external surface of theabrasive particles. In certain embodiments, the bonding layer can beformed such that it overlies at least 90% of the exterior surface of theabrasive article preform and the finally-formed abrasive article. Inother embodiments, the coverage of the bonding layer can be greater,such that it overlies at least about 92%, at least about 95%, or even atleast about 97% of the entire abrasive article preform andfinally-formed abrasive article. In one particular embodiment, thebonding layer can be formed such that it overlies essentially all of theexternal surfaces of the abrasive article. Still, in an alternativeembodiment, the bonding layer can be selectively placed, such thatexposed regions can be formed on the abrasive article.

The bonding layer can be made of a particular material, such as anorganic material, inorganic material, and a combination thereof. Somesuitable organic materials can include polymers such as a UV curablepolymer, thermosets, thermoplastics, and a combination thereof. Someother suitable polymer materials can include urethanes, epoxies,polyimides, polyamides, acrylates, polyvinyls, and a combinationthereof.

Suitable inorganic materials for use in the bonding layer can includemetals, metal alloys, cermets, ceramics, composites, and a combinationthereof. In one particular instance, the bonding layer can be formed ofa material having at least one transition metal element, and moreparticularly, a metal alloy containing a transition metal element. Somesuitable transition metal elements for use in the bonding layer caninclude nickel, lead, silver, copper, zinc, tin, titanium, molybdenum,chromium, iron, manganese, cobalt, niobium, tantalum, tungsten,palladium, platinum, gold, ruthenium, or a combination thereof. Incertain instances, the bonding layer can include nickel, and may be ametal alloy comprising nickel, or even a nickel-based alloy. In stillother embodiments, the bonding layer can consist essentially of nickel.

In accordance with one embodiment, the bonding layer can be made of amaterial, including for example, composite materials, having a hardnessthat is greater than a hardness of the tacking material. For example,the bonding layer can have a Vickers hardness that is at least about 5%harder than a Vickers hardness of the tacking material based on theabsolute values of the equation ((Hb−Ht)/Hb)×100%, wherein Hb representsthe hardness of the bonding layer and Ht represents the hardness of thetacking layer. In one embodiment, the bonding layer can be at leastabout 10% harder, such as at least about 20% harder, at least about 30%harder, at least about 40% harder, at least about 50% harder, at leastabout 75% harder, at least about 90% harder, or even at least about 99%harder than the hardness of the tacking layer. Yet, in anothernon-limiting embodiment, the bonding layer may be not greater than about99% harder, such as not greater than about 90% harder, not greater thanabout 80% harder, not greater than about 70% harder, not greater thanabout 60% harder, not greater than about 50% harder, not greater thanabout 40% harder, not greater than about 30% harder, not greater thanabout 20% harder, not greater than about 10% harder than the hardness ofthe tacking material. It will be appreciated that the difference betweenthe hardness of the bonding layer and the tacking material can be withina range between any of the above minimum and maximum percentages.

Additionally, the bonding layer can have a fracture toughness (K1c) asmeasured by indentation method, that is at least about 5% greater thanan average fracture toughness of the tacking material based on theabsolute values of the equation ((Tb−Tt)/Tb)×100%, wherein Tb representsthe fracture toughness of the bonding layer and Tt represents thefracture toughness of the tacking material. In one embodiment, thebonding layer can have a fracture toughness of at least about 8%greater, such as at least about 10% greater, at least about 15% greater,at least about 20% greater, at least about 25% greater, at least about30% greater, or even at least about 40% greater than the fracturetoughness of the tacking material. Yet, in another non-limitingembodiment, the fracture toughness of the bonding layer may be notgreater than about 90% greater, such as not greater than about 80%greater, not greater than about 70% greater, not greater than about 60%greater, not greater than about 50% greater, not greater than about 40%greater, not greater than about 30% greater, not greater than about 20%greater, or even not greater than about 10% greater than the fracturetoughness of the tacking material. It will be appreciated that thedifference between the fracture toughness of the bonding layer and thefracture toughness of the tacking material can be within a range betweenany of the above minimum and maximum percentages.

Optionally, the bonding layer can include a filler material. The fillercan be various materials suitable for enhancing performance propertiesof the finally-formed abrasive article. Some suitable filler materialscan include abrasive particles, pore-formers such as hollow sphere,glass spheres, bubble alumina, natural materials such as shells and/orfibers, metal particles, graphite, lubricious material and a combinationthereof.

In one particular embodiment, the bonding layer can be formed by anelectrolytic plating process and one or more additives, such as wettingagents, hardeners, stress reducers and leveling agents, can be includedin the plating solution to produce bonding layer with desired propertiesand may facilitate performance of the abrasive article. For example,additives containing sulfur or materials that will form sulfur in thefinally-formed layer can be included in the plating solution to producebonding layer with sulfur for controlled hardness and tensile stress.Some suitable examples of such additives can include saccharin,metabenzene disulfonic acid, sodium benzene sulfonate, and the like. Thebonding layer may include a particular content of sulfur, such as atleast 50 ppm sulfur for a total weight of the bonding layer. Still, inother instances, the content of the sulfur in the bonding layer can begreater, such as at least 60 ppm or at least 70 ppm or at least 80 ppmor at least 90 ppm or at least 100 ppm or at least 120 ppm or at least140 ppm or at least 160 ppm or at least 180 ppm or at least 200 ppm orat least 250 ppm or at least 300 ppm or at least 350 ppm or at least 400ppm for a total weight of the bonding layer. Still, in at least onenon-limiting embodiment, the content of the sulfur in the bonding layercan be not greater than 2000 ppm, such as not greater than 1500 ppm ornot greater than 1000 ppm or not greater than 900 ppm or not greaterthan 800 ppm or not greater than 700 ppm or not greater than 600 ppm ornot greater than 500 ppm for a total weight of the bonding layer. Itwill be appreciated that the content of sulfur in the bonding layer canbe within a range including any of the minimum and maximum percentagesnoted above.

In one particular embodiment, the bonding layer can include a filler inthe form of abrasive particles, which can be the same as or differentfrom the abrasive particles 212 contained in the mixture and attached tothe substrate 201. The abrasive particle filler can be significantlydifferent than the abrasive particles 212, particularly with regard tosize, such that in certain instances the abrasive particle filler canhave an average particle size that is substantially less than theaverage particle size of the abrasive particles 212. For example, theabrasive particle filler can have an average grain size that is at leastabout 2 times less than the average particle size of the abrasiveparticles 212. In fact, the abrasive filler may have an average particlesize that is even smaller, such as on the order of at least 3 timesless, such as at least about 5 times less, at least about 10 times less,and particularly within a range between about 2 times and about 10 timesless than the average particle size of the abrasive particles 212.

The abrasive grain filler within the bonding layer can be made from amaterial such as carbides, carbon-based materials (e.g. fullerenes),diamond, borides, nitrides, oxides, oxynitrides, oxyborides, and acombination thereof. In particular instances, the abrasive grain fillercan be a superabrasive material such as diamond, cubic boron nitride, ora combination thereof.

After forming the bonding layer at step 106, the process may optionallyinclude forming a coating layer overlying the bonding layer. In at leastone instance, the coating layer can be formed such that it is in directcontact with at least a portion of the bonding layer. Forming of thecoating layer can include a deposition process. Some suitable depositionprocesses can include plating (electrolyte or electroless), spraying,dipping, printing, coating, and a combination thereof.

The coating layer can include an organic material, an inorganicmaterial, and a combination thereof. According to one aspect, thecoating layer can include a material such as a metal, metal alloy,cermet, ceramic, organic, glass, and a combination thereof. Moreparticularly, the coating layer can include a transition metal element,including for example, a metal from the group of titanium, vanadium,chromium, molybdenum, iron, cobalt, nickel, copper, silver, zinc,manganese, tantalum, tungsten, and a combination thereof. For certainembodiments, the coating layer can include a majority content of nickel,and in fact, may consist essentially of nickel. Alternatively, thecoating layer can include a thermoset, a thermoplastic, and acombination thereof. In one instance, the coating layer includes a resinmaterial and may be essentially free of a solvent.

In one particular embodiment, the coating layer can include a fillermaterial, which may be a particulate material. For certain embodiments,the coating layer filler material can be in the form of abrasiveparticles, which may be the same as or different from the abrasiveparticles 212 attached to the substrate 201. Certain suitable types ofabrasive particles for use as the coating layer filler material caninclude carbides, carbon-based materials (e.g., diamond), borides,nitrides, oxides, and a combination thereof. Some alternative fillermaterials can include pore-formers such as hollow sphere, glass spheres,bubble alumina, natural materials such as shells and/or fibers, metalparticles, and a combination thereof.

The coating filler material may be significantly different than theabrasive particles 212, particularly with regard to size, such that incertain instances the coating layer filler material can have an averageparticle size that is substantially less than the average particle sizeof the abrasive particles 212. For example, the coating layer fillermaterial can have an average particle size that is at least about 2times less than the average particle size of the abrasive particles 212.In fact, the coating layer filler material may have an average particlesize that is even smaller, such as on the order of at least 3 timesless, such as at least about 5 times less, at least about 10 times less,and particularly within a range between about 2 times and about 10 timesless than the average particle size of the abrasive particles 212.

FIG. 3 includes a cross-sectional illustration of an abrasive articleformed according to an embodiment. As illustrated, the abrasive article300 can include a substrate 201, which is in the form of an elongatedbody, such as a wire. As further illustrated, the abrasive article 300can include a plurality of discrete tacking regions 303 overlying theexternal surface of the substrate 201. The abrasive article 300 canfurther include abrasive particles 212, which can be bonded to thesubstrate 201 at the discrete tacking regions 303. The abrasive article300 can further include discrete formations 305 which can overlie thesubstrate 201. Moreover, the abrasive article 300 can include a bondinglayer 301 overlying the substrate 201, abrasive particles 212, discretetacking regions 303 and discrete formations 305. While not illustrated,it will be appreciated that the abrasive article may include othercomponent layers described herein, including for example, a barrierlayer, coating layer, and the like.

According to one embodiment, the discrete tacking regions 303 can bedefined by discrete portions of the tacking material 304, which may bebonded to an abrasive particle 212 for provisional bonding of theabrasive particles 212 to the substrate 201 during processing. Due tothe method of processing, the particulate material closest to theabrasive particles during treatment may preferentially gather around theabrasive particles, thus forming discrete tacking regions as opposed toa continuous and conformal coating of tacking material 304. Accordingly,the discrete tacking regions 303 can include a tacking material 304,wherein the tacking material has any of the features of the tackingmaterial described herein. For example, as illustrated, the discretetacking regions 303 can be a discontinuous distribution of features,such as the portions of the tacking material 304 overlying thesubstrate. In certain instances, at least one discrete tacking regioncan be isolated and spaced apart from another discrete tacking region,such that the region between the discrete tacking regions is essentiallyfree of tacking material 304. Accordingly, the tacking material 304 onthe surface of the substrate 201 defines a discontinuous layer, definingopenings or gaps wherein the upper surface of the substrate 201 can beessentially free of the tacking material 304. The discrete tackingregions 303 can be bonded directly to the substrate 201. For oneembodiment, essentially the entire abrasive article can include discretetacking regions 303 and the abrasive article 303 can be essentially freeof a continuous layer of tacking material 304.

At least a portion discrete tacking regions 303 can be separated fromeach other by gap regions 307, which define portions of the abrasivearticle where there is no tacking material 304 underlying the bondinglayer 301. Accordingly, the bonding layer 301 can be in direct contactwith and bonded directly to the substrate 201 in the gap regions 307. Incertain instances, the abrasive article 300 may have a greater content(as measured in area) of the gap regions 307 on the surface of theabrasive article 300 compared to the content of discrete tacking regions303. In still other embodiments, the abrasive article 300 may have agreater content (as measured in area) of the discrete tacking regions303 on the surface of the abrasive article 300 compared to the contentof gap regions 307.

Furthermore, as illustrated in FIG. 3, the discrete tacking regions 303can be randomly distributed on the surface of the substrate 201.Accordingly, the size and arrangement of the discrete tacking regions303 may be random. Moreover, the size and arrangement of the gap regions307 may also be random.

In one embodiment, the abrasive article 300 includes discrete formations305 overlying the substrate 201, and more particularly, bonded directlyto the substrate 201. Each of the discrete formations 305 can be bondeddirectly to the substrate 201. According to one embodiment, at least oneof the discrete formations 305 can include a metal material. Moreparticularly, each of the discrete formations 305 can include a metalmaterial, such as the tacking material 304. In at least one embodiment,the discrete formations 305 can consist essentially of the tackingmaterial 303, and may have essentially the same composition as thetacking material 304 of the discrete tacking regions 304. The discreteformations 305 can include the tacking material 304 and can have any ofthe features of the tacking material 304 as described in embodimentsherein. For example, the discrete formations can include a soldermaterial, may include tin, and more particularly, may consistessentially of tin. The discrete tacking regions 303 and discreteformations 305 may include a material that is essentially free of anintermetallic material.

As illustrated in FIG. 3, the discrete formations 305 may be randomlydistributed on the surface of the substrate 201. Accordingly, the sizeand arrangement of the discrete formations 305 may be random. Moreover,the size and arrangement of the gap regions 307 may also be random. Asfurther illustrated, the discrete formations 305 may vary in size andshape with respect to each other.

In one embodiment, at least one discrete formation 305 can be separatefrom another discrete formation by a gap region 307. That is, a gapregion 307 can extend between and separate at least two discreteformations 305, such that there is a gap in the material forming each ofthe discrete formations 305 that is filled by the bonding layer 301.Moreover, at least one discrete formation 305 can be separated from adiscrete tacking region 303 by a gap region. Likewise, a gap region 307can extend between and separate the discrete formation 305 from thediscrete tacking region 303, such that there is a gap in the materialforming the discrete formation 305 and discrete tacking region 303 thatis filled by the bonding layer 301. In at least one embodiment, thediscrete formations 305 can be essentially free of abrasive particles212.

In at least one embodiment, the discrete formations 305 can have agenerally rounded shape, as viewed in cross-section and/or top down. Thediscrete formations 305 may be formed form the particulate duringprocessing that was not near an abrasive particle, but due to processingconditions, accumulated at a location on the surface of the substrate201. Accordingly, the discrete formations 305 can be spaced apart fromthe abrasive particles, and may be characterized as regions on thesurface of the substrate 201 that are not bonded to or associated withan abrasive particle. By contrast, the discrete tacking regions 303 arediscrete or isolated regions on the surface of the substrate 201 andhave at least one abrasive particle that is associated with the regionand bonded therein.

Without wishing to be tied to a particular theory, it is thought thatthe existence of the discrete formations 305 may act as crack arrestorsduring operation of the abrasive article for any cracks that may beinitiated in the bonding layer. Unlike a continuous coating of material,the discontinuous coating of tacking material characterized by thediscrete tacking regions 303 and discrete formations 305 may improvecrack arresting and improve the abrasive capabilities of the abrasivearticle.

As further illustrated, the bonding layer 301 can be overlying thesubstrate 201, abrasive particles 212, discrete tacking regions 303, anddiscrete formations 305. In particular instances, the bonding layer 301can be in direct contact with and bonded directly to the substrate 201,abrasive particles 212, discrete tacking regions 303, and discreteformations 305.

According to another embodiment, the abrasive article 300 may include aparticular content of metal material (e.g., tacking material) in theplurality of discrete tacking regions 303 and plurality of discreteformations 305 that may facilitate improved manufacturing and/orperformance. For example, the abrasive article 300 can include a contentof metal (Cmm) in the in the plurality of discrete tacking regions 303and plurality of discrete formations 305 of not greater than 2 g/km,wherein Cmm is measured as grams of metal material per kilometer of thelength of the abrasive article 300. In still another embodiment, thecontent of metal material ( Cmm) can be not greater than 1 g/km or notgreater than 0.8 g/km or not greater than 0.6 g/km or not greater than0.4 g/km or not greater than 0.2 g/km or not greater than 0.1 g/km ornot greater than 0.08 g/km or not greater than 0.06 g/km or not greaterthan 0.04 g/km or not greater than 0.02 g/km or even not greater than0.01 g/km. Still, in another non-limiting embodiment, the content ofmetal material (Cmm) in the plurality of discrete tacking regions 303and plurality of discrete formations 305 can be at least 0.001 g/km,such as at least 0.002 g/km or at least 0.004 g/km or at least 0.006g/km or at least 0.008 g/km or at least 0.01 g/km or at least 0.02 g/kmor at least 0.04 g/km or at least 0.06 g/km or at least 0.08 g/km or atleast 0.01 g/km. It will be appreciated that the content of metalmaterial (Cmm) in the in the plurality of discrete tacking regions 303and plurality of discrete formations 305 can be within a range includingany of the minimum and maximum values noted above.

In still another embodiment, the abrasive article 300 may be formed tohave a particular relationship between the content of metal (Cmm) andthe content of abrasive particles 212, which can be represented by Cap,wherein Cap defines the grams of abrasive particles 212 per kilometer oflength of the abrasive article 300. The Cmm and Cap of an abrasivearticle 300 may be calculated by any standard analysis method, such as,inductively coupled plasma mass spectrometry. In particular, thefollowing method may be used to calculate the Cmm and Cap of an abrasivearticle: 1) a set length of abrasive article 300 may be dissolved in hotacid, 2) the abrasive grains may be retrieved through filtering andtheir weight determined, 3) the weight of the metal (i.e., tackingmaterial) in the acid solution may be determined using inductivelycoupled plasma spectrometry, and 4) the Cmm and Cap per the set lengthof abrasive article 300 may be calculated. According to one embodiment,the abrasive article can be formed to have a particular ratio (Cmm/Cap)of not greater than 1, such as not greater than 0.9 or not greater than0.8 or not greater than 0.7 or not greater than 0.6 or not greater than0.5 or not greater than 0.4 or not greater than 0.3 or not greater than0.2 or not greater than 0.18 or not greater than 0.16 or not greaterthan 0.15 or not greater than 0.014 or not greater than 0.13 or nogreater than 0.12 or not greater than 0.11 or not greater than 0.1 ornot greater than 0.09 or not greater than 0.08 or not greater than 0.07or not greater than 0.06 or no greater than 0.05 or not greater than0.04 or not greater than 0.03 or even not greater than 0.02. In yetanother non-limiting embodiment, the abrasive article 300 may be formedto have a ratio (Cmm/Cap) of at least 0.002, such as at least 0.004 orat least 0.006 or at least 0.008 or at least 0.01 or at least 0.02 or atleast 0.03 or at least 0.04 or at least 0.05 or at least 0.06 or atleast 0.07 or at least 0.08 or at least 0.09 or at least 0.1 or at least0.12 or at least 0.14 or at least 0.16 or at least 0.18 or at least 0.2or at least 0.3 or at least 0.4 or at least 0.5 or at least 0.6 or atleast 0.7 or at least 0.8 or at least 0.9. It will be appreciated thatthe ratio (Cmm/Cap) can be within a range including any of the minimumand maximum values noted above, including for example, at least 0.002and not greater than 1, even at least 0.01 and not greater than 0.5 oreven at least 0.025 and not greater than 0.25.

In another embodiment, the abrasive article 300 may be formed to have aparticular tacking material coverage (TMc), which may be defined as thepercent of the substrate surface covered with tacking material. The TMcof an abrasive article 300 may be determined by making a samplecross-section of the abrasive article 300 and taking a scanning electronmicroscopy or energy dispersive X-ray spectroscopy image of the crosssection at a magnification of 400×. The substrate, tacking material andcoating material will be shown in different colors on the images. Thecalculation of TMc is based on the equation TMc=((TS_(c)/S_(c))*100),where S_(C) is the circumference of the substrate as measured on theimage of the cross section at a magnification of 400× using imageanalysis software (e.g., ImageJ image analysis software) and TS_(C) issum of the lengths of all portions of the circumference of the substratethat are covered by tacking material as measured on the image of thecross section at a magnification of 400× using image analysis software(e.g., ImageJ image analysis software). The TMc for an abrasive articleshould be calculated as the average TMc of a statistically relevantsample size of cross-section images at different locations along thelength of the abrasive article 300. According to one embodiment, theabrasive article 300 may be formed to have a particular TMc of notgreater than about 50%, such as, not greater than about 45%, not greaterthan about 40%, not greater than about 35%, not greater than about 30%,not greater than about 25%, not greater than about 20%, not greater thanabout 15%, not greater than about 10% or even not greater than about 5%.According to still another embodiment, the abrasive article 300 may beformed to have a particular TMc of at least about 0.01%, such as, atleast about 0.1% or even at least about 1%. It will be appreciated thatthe TMc of an abrasive article 300 may be within a range including anyof the minimum and maximum values noted above.

The bonding layer 301 can be in the form of a continuous coating and mayhave a particular relationship in terms of thickness relative to theaverage particle size of the abrasive particle 212. For example, thebonding layer 301 can have an average thickness of at least about 5% ofan average particle size of the abrasive particles 212. The relativeaverage thickness of the bonding layer 301 to the average particle sizecan be calculated by the absolute value of the equation (Tb/Tp)×100%,wherein Tp represents the average particle size and Tb represents theaverage thickness of the bonding layer 301. In other embodiments, theaverage thickness of the bonding layer 301 can be greater, such as atleast about 8%, at least about 10%, at least about 15%, or even at leastabout 20%. Still, in another non-limiting embodiment, the averagethickness of the bonding layer 301 can be limited, such that it is notgreater than about 50%, not greater than about 40%, not greater thanabout 30%, or even not greater than about 20% of the average particlesize of the abrasive particles 212. It will be appreciated that thebonding layer 301 can have an average thickness within a range includingany of the minimum and maximum percentages noted above.

In more particular instances, the bonding layer 205 can be formed tohave an average thickness that is at least 1 micron. For other abrasivearticles, the bonding layer 205 can have a greater average thickness,such as at least about 2 microns, at least about 3 microns, at leastabout 4 microns, at least about 5 microns, at least about 7 microns, oreven at least about 10 microns. Particular abrasive articles can have abonding layer 205 having an average thickness that is not greater thanabout 60 microns, such as not greater than about 50 microns, such as notgreater than about 40 microns, not greater than about 30 microns, oreven not greater than about 20 microns. It will be appreciated that thebonding layer 205 can have an average thickness within a range betweenany of the minimum and maximum values noted above.

In another aspect, the abrasive article 300 can be formed to have aparticular concentration of abrasive particles 212, which may facilitateimproved performance of the abrasive article. According to oneembodiment, the abrasive article 300 can have an abrasive particleconcentration of at least 10 particles per mm of substrate, such as atleast 20 particles per mm of substrate or at least 30 particles per mmof substrate or even at least 40 particles per mm of substrate. In stillanother non-limiting embodiment, the abrasive particle concentration canbe not greater than 800 particles per mm, such as not greater than 700particles per mm or not greater than 600 particles per mm or not greaterthan 500 particles per mm or not greater than 400 particles per mm ornot greater than 300 particles per mm or not greater than 200 particlesper mm. It will be appreciated that the abrasive particle concentrationcan be within a range including any of the minimum and maximum valuesnoted above.

In still another embodiment, the abrasive article 300 can be formed tohave a particular concentration of abrasive particles 212, which mayfacilitate improved performance of the abrasive article. According toone embodiment, the abrasive article 300 can have an abrasive particleconcentration of at least 0.5 carats per kilometer of the abrasivearticle, such as at least 1.0 carats per kilometer, at least about 1.5carats per kilometer of the abrasive article, at least 5 carats perkilometer, at least about 10 carats per kilometer of the abrasivearticle, at least 15 carats per kilometer or even at least about 20carats per kilometer of the abrasive article. In still anothernon-limiting embodiment, the abrasive particle concentration can be notgreater than 30 carats per kilometer, such as not greater than 25 caratsper kilometer or not greater than 20 carats per kilometer or not greaterthan 18 carats per kilometer or not greater than 16 carats per kilometeror even not greater than 14 carats per kilometer or not greater than 12carats per kilometer or not greater than 10 carats per kilometer or notgreater than 8 carats per kilometer or even not greater than 6 caratsper kilometer. It will be appreciated that the abrasive particleconcentration can be within a range including any of the minimum andmaximum values noted above.

In another embodiment, the abrasive article 300 may be formed to have aparticular abrasive particle surface agglomeration (APsa). The APsa maybe calculated by visually inspecting the surface of a portion of asubstrate having at least 100 abrasive particles 212 attached thereto.The visual inspection should be conducted under a magnification of 400×.The calculation of APsa is based on the equation APsa=((TAP/TP)*100),where TP is the total number of abrasive particles on the visuallyinspected surface (i.e. at least 100 abrasive particles) and TAP is thetotal number of agglomerated particles on the visually inspectedsurface. An agglomerated abrasive particle is defined as any abrasiveparticle 212 on the visually inspected surface of a substrate where thebonding layer 205 overlying the abrasive particle 212 directly contactsthe bonding layer 205 overlying at least one other abrasive particle212. For purposes of illustration, FIG. 12 includes an image of aportion of abrasive article 300 under a magnification of 400×. Asdefined herein, abrasive particles 212 a are examples of abrasiveparticles that are not agglomerated abrasive particles on the surface ofabrasive article 300 and abrasive particles 212 b are examples ofabrasive particles that are agglomerated abrasive particles on thesurface of abrasive article 300. In one embodiment, an abrasive article300 may be formed to have a particular APsa of not greater than about60%, such as, not greater than about 50%, not greater than about 40%,not greater than about 30%, not greater than about 20% or even notgreater than about 10%. It will be appreciated that the APsa can bewithin a range including any of the values noted above.

FIG. 4 includes an image of a portion of an abrasive article accordingto an embodiment. FIG. 5 includes a cross-sectional image of a portionof the abrasive article of FIG. 4. FIG. 6 includes a cross-sectionalimage of a portion of the abrasive article of FIG. 4. As illustrated,the abrasive article 400 can include a substrate 401, abrasive particles412 attached to the substrate 401 at discrete tacking regions 403. Asfurther illustrated, the abrasive article 400 can include a plurality ofdiscrete formations 405, which can be bonded directly to the surface ofthe substrate 401, and moreover, can be spaced apart from each other andthe discrete tacking regions 403 by gap regions 420. Accordingly, theabrasive article 400 includes a discontinuous tacking layer comprising aplurality of discrete tacking regions 403 associated with and bonded tothe abrasive particles 412 and further comprising discrete formations405 which are spaced apart from the abrasive particles 412 and thediscrete tacking regions 403.

As illustrated, and according to one embodiment, the discrete tackingregions 403 may have an average length as viewed in cross-section thatis substantially the same as the length of the abrasive particles 412 towhich they are bonded. By contrast, the discrete formations 403 may havea greater variety in shape and size, and may be larger or smaller thanthe discrete tacking regions 403 and the average particle size of theabrasive particles 412.

As further illustrated in FIGS. 5 and 6, the abrasive article 400 caninclude interfaces of direct contact between the bonding layer 407 andthe substrate 401. Furthermore, at the periphery of the discrete tackingregions 403, the abrasive article 400 also includes triple-pointboundaries including direct contact between the bonding layer 407,substrate 401 and tacking material of the discrete tacking regions 403.Moreover, at the periphery of the discrete formations 405, the abrasivearticle 400 can have a triple-point boundary including direct contactbetween the bonding layer 407, substrate 401 and material (e.g., tackingmaterial) of the discrete formation 405.

The abrasive articles of the embodiments herein may be wire saws thatare particularly suited for slicing of workpieces. The workpieces can bevarious materials, including but not limited to, ceramic, semiconductivematerial, insulating material, glass, natural materials (e.g., stone),organic material, and a combination thereof. More particularly, theworkpieces can include oxides, carbides, nitrides, minerals, rocks,single crystalline materials, multicrystalline materials, and acombination thereof. For at least one embodiment, an abrasive article ofan embodiment herein may be suitable for slicing a workpiece ofsapphire, quartz, silicon carbide, and a combination thereof.

According to at least one aspect, the abrasive articles of theembodiments can be used on particular machines, and may be used atparticular operating conditions that have improved and unexpectedresults compared to conventional articles. While not wishing to be boundto a particular theory, it is thought there may be some synergisticeffect between the features of the embodiments.

Generally, cutting, slicing, bricking, squaring, or any other operationcan be conducted by moving the abrasive article (i.e., wire saw) and theworkpiece relative to each other. Various types and orientations of theabrasive articles relative to the workpieces may be utilized, such thata workpiece is sectioned into wafers, bricks, rectangular bars,prismatic sections, and the like.

This may be accomplished using a reel-to-reel machine, wherein movingcomprises reciprocating the wire saw between a first position and asecond position. In certain instances, moving the abrasive articlebetween a first position and a second position comprises moving theabrasive article back and forth along a linear pathway. While the wireis being reciprocated, the workpiece may also be moved, including forexample, rotating the workpiece.

Alternatively, an oscillating machine may be utilized with any abrasivearticle according to the embodiments herein. Use of an oscillatingmachine can include moving the abrasive article relative to theworkpiece between a first position and second position. The workpiecemay be moved, such as rotated, and moreover the workpiece and wire canboth be moved at the same time relative each other. An oscillatingmachine may utilize a back and forth motion of the wire guide relativeto the workpiece, wherein a reel-to-reel machine does not necessarilyutilize such a motion.

For some applications, during the slicing operation the process mayfurther include providing a coolant at an interface of the wire saw andworkpiece. Some suitable coolants include water-based materials,oil-based materials, synthetic materials, and a combination thereof.

In certain instances, slicing can be conducted as a variable rateoperation. The variable rate operation can include moving the wire andworkpiece relative to each other for a first cycle and moving the wireand workpiece relative to each other for a second cycle. Notably, thefirst cycle and the second cycle may be the same or different. Forexample, the first cycle can include translation of the abrasive articlefrom a first position to a second position, which in particular, mayinclude translation of the abrasive article through a forward andreverse direction cycle. The second cycle can include translation of theabrasive article from a third position to a fourth position, which mayalso include translation of the abrasive article through a forward andreverse direction cycle. The first position of the first cycle can bethe same as the third position of the second cycle, or alternatively,the first position and the third position may be different. The secondposition of the first cycle can be the same as the fourth position ofthe second cycle, or alternatively, the second position and the fourthposition may be different.

According to a particular embodiment, the use of an abrasive article ofan embodiment herein in a variable rate cycle operation can include afirst cycle that includes the elapsed time to translate the abrasivearticle from a starting position in a first direction (e.g., forward) toa temporary position, and in a second direction (e.g., backward) fromthe temporary position, thus returning to the same starting position orclose to the starting position. Such a cycle can include the durationfor accelerating the wire from 0 m/s to set wire speed in the forwarddirection, the elapsed time for moving the wire at set wire speed in theforward direction, the elapsed time on decelerating the wire from setwire speed to 0 m/s in the forward direction, the elapsed time onaccelerating the wire from 0 m/s to set wire speed in the backwarddirection, the elapsed time on moving the wire at set wire speed in thebackward direction, and the elapsed time on decelerating the wire fromset wire speed to 0 m/s in the backward direction.

According to one particular embodiment, the first cycle can be at leastabout 30 seconds, such as at least about 60 seconds, or even t leastabout 90 seconds. Still, in one non-limiting embodiment, the first cyclecan be not greater than about 10 minutes. It will be appreciated thatthe first cycle can have a duration within a range between any of theminimum and maximum values above.

In yet another embodiment, the second cycle can be at least about 30seconds, such as at least about 60 seconds, or even at least about 90seconds. Still, in one non-limiting embodiment, the second cycle can benot greater than about 10 minutes. It will be appreciated that thesecond cycle can have a duration within a range between any of theminimum and maximum values above.

The total number of cycles in a for a cutting process may vary, but canbe at least about 20 cycles, at least about 30 cycles, or even at leastabout 50 cycles. In particular instances, the number of cycles may benot greater than about 3000 cycles or even not greater than about 2000cycles. The cutting operation may last for a duration of at least about1 hour or even at least about 2 hours. Still, depending upon theoperation, the cutting process may be longer, such as at least about 10hours, or even 20 hours of continuous cutting.

In certain cutting operations, the wire saw of any embodiment herein maybe particularly suited for operation at a particular feed rate. Forexample, the slicing operation can be conducted at a feed rate of atleast about 0.05 mm/min, at least about 0.1 mm/min, at least about 0.5mm/min, at least about 1 mm/min, or even at least about 2 mm/min. Still,in one non-limiting embodiment, the feed rate may be not greater thanabout 20 mm/min. It will be appreciated that the feed rate can be withina range between any of the minimum and maximum values above.

For at least one cutting operation, the wire saw of any embodimentherein may be particularly suited for operation at a particular wiretension. For example, the slicing operation can be conducted at a wiretension of at least about 30% of a wire break load, such as at leastabout 50% of the wire break load, or even at least about 60% of a breakload. Still, in one non-limiting embodiment, the wire tension may be notgreater than about 98% of the break load. It will be appreciated thatthe wire tension can be within a range between any of the minimum andmaximum percentages above.

According to another cutting operation, the abrasive article can have aVWSR range that facilitates improved performance. VWSR is the variablewire speed ratio and can generally be described by the equationt2/(t1+t3), wherein t2 is the elapsed time when the abrasive wire movesforward or backward at a set wire speed, wherein t1 is the elapsed timewhen the abrasive wire moves forward or backward from 0 wire speed toset wire speed, and t3 is the elapsed time when the abrasive wire movesforward or backward from constant wire speed to 0 wire speed. Forexample, the VWSR range of a wire saw according to an embodiment hereincan be at least about 1, at least about 2, at least about 4, or even atleast about 8. Still, in one non-limiting embodiment, the VWSR rate maybe not greater than about 75 or even not greater than about 20. It willbe appreciated that the VWSR rate can be within a range between any ofthe minimum and maximum values above. In one embodiment, an exemplarymachine for variable wire speed ratio cutting operations can be a MeyerBurger DS265 DW Wire Saw machine.

Certain slicing operations may be conducted on workpieces includingsilicon, which can be single crystal silicon or multicrystallinesilicon. According to one embodiment, use of an abrasive articleaccording to an embodiment demonstrates a life of at least about 8m²/km, such as at least about 10 m²/km, at least about 12 m²/km, or evenat least about 15 m²/km. The wire life can be based upon the wafer areagenerated per kilometer of abrasive wire used, wherein wafer areagenerated is calculated based on one side of the wafer surface. In suchinstances, the abrasive article may have a particular abrasive particleconcentration, such as at least about 0.5 carats per kilometer of thesubstrate, at least about 1.0 carats per kilometer of substrate, atleast about 1.5 carats per kilometer of substrate, or even at leastabout 2.0 carats per kilometer of substrate. Still, the concentrationmay be not greater than about 20 carats per kilometer of substrate, oreven not greater than about 10 carats per kilometer of substrate. Theaverage particle size of the abrasive particles can be less than about20 microns. It will be appreciated that the abrasive particleconcentration can be within a range between any of the minimum andmaximum values above. The slicing operation may be conducted at a feedrate as disclosed herein.

According to another operation, a silicon workpiece including singlecrystal silicon or multicrystalline silicon can be sliced with anabrasive article according to one embodiment, and the abrasive articlecan have a life of at least about 0.5 m2/km, such as at least about 1m²/km, or even at least about 1.5 m²/km. In such instances, the abrasivearticle may have a particular abrasive particle concentration, such asat least about 0.5 carats per kilometer of the substrate, at least about1 carats per kilometer of substrate, of at least about 2 carats perkilometer of substrate, at least about 3 carats per kilometer ofsubstrate. Still, the concentration may be not greater than about 30carats per kilometer of substrate, or even not greater than about 15carats per kilometer of substrate. The average particle size of theabrasive particles can be less than about 20 microns. It will beappreciated that the abrasive particle concentration can be within arange between any of the minimum and maximum values above.

The slicing operation may be conducted at a feed rate of at least about0.5 mm/min, at least about 1 mm/min, at least about 2 mm/min, at leastabout 3 mm/min. Still, in one non-limiting embodiment, the feed rate maybe not greater than about 20 mm/min. It will be appreciated that thefeed rate can be within a range between any of the minimum and maximumvalues above.

According to another operation, a sapphire workpiece can be sliced usingan abrasive article of an embodiment herein. The sapphire workpiece mayinclude a c-plane sapphire, an a-plane sapphire, or a r-plane sapphirematerial. For at least one embodiment, the abrasive article can slicethrough the sapphire workpiece and exhibit a life of at least about 0.1m²/km, such as at least about 0.2 m²/km, at least about 0.3 m²/km, atleast about 0.4 m²/km, or even at least about 0.5 m²/km. In suchinstances, the abrasive article may have a particular abrasive particleconcentration, such as at least about 5 carats per kilometer of thesubstrate, at least about 10 carats per kilometer of substrate, of atleast about 20 carats per kilometer of substrate, at least about 40carats per kilometer of substrate. Still, the concentration may be notgreater than about 300 carats per kilometer of substrate, or even notgreater than about 150 carats per kilometer of substrate. The averageparticle size of the abrasive particles can be greater than about 20microns. It will be appreciated that the abrasive particle concentrationcan be within a range between any of the minimum and maximum valuesabove.

The foregoing slicing operation on the workpiece of sapphire may beconducted at a feed rate of at least about 0.05 mm/min, such as at leastabout 0.1 mm/min, or even at least about 0.15 mm/min. Still, in onenon-limiting embodiment, the feed rate may be not greater than about 2mm/min. It will be appreciated that the feed rate can be within a rangebetween any of the minimum and maximum values above.

In yet another aspect, the abrasive article may be used to slice throughworkpieces including silicon carbide, including single crystal siliconcarbide. For at least one embodiment, the abrasive article can slicethrough the silicon carbide workpiece and exhibit a life of at leastabout 0.1 m²/km, such as at least about 0.2 m²/km, at least about 0.3m²/km, at least about 0.4 m²/km, or even at least about 0.5 m²/km. Insuch instances, the abrasive article may have a particular abrasiveparticle concentration, such as at least about 1 carat per kilometer ofthe substrate, at least about 2 carats per kilometer of substrate, of atleast about 3 carats per kilometer of substrate, at least about 4 caratsper kilometer of substrate. Still, the concentration may be not greaterthan about 50 carats per kilometer of substrate, or even not greaterthan about 30 carats per kilometer of substrate. It will be appreciatedthat the abrasive particle concentration can be within a range betweenany of the minimum and maximum values above.

The foregoing slicing operation on the workpiece of silicon carbide maybe conducted at a feed rate of at least about 0.05 mm/min, such as atleast about 0.10 mm/min, or even at least about 0.15 mm/min. Still, inone non-limiting embodiment, the feed rate may be not greater than about2 mm/min. It will be appreciated that the feed rate can be within arange between any of the minimum and maximum values above.

According to yet another embodiment, abrasive articles according toembodiments described herein may be produced at a certain productionrate. The production rate of embodiments of abrasive articles describedherein may be the speed of formation of an abrasive article, in metersof substrate per minute, wherein the abrasive article includes asubstrate having an elongated body, a tacking layer overlying thesubstrate, abrasive particle overlying the tacking layer and defining afirst abrasive particle concentration at least about 10 particles per mmof substrate, and the formation of the bonding layer. In certainembodiments, the production rate may be at least about 10 meters perminute, such as, at least about 12 meters per minute, at least about 14meters per minute, at least about 16 meters per minute, at least about18 meters per minute, at least about 20 meters per minute, at leastabout 25 meters per minute, at least about 30 meters per minute, atleast about 40 meters per minute or even at least about 60 meters perminute.

In particular instances, it is noted that the present method can be usedto facilitate efficient production of abrasive wire saws having a highconcentration of abrasive particles. For example, the abrasive articlesof the embodiments herein having any of the featured abrasive particleconcentrations can be formed at any of the foregoing production rateswhile maintaining or exceeding performance parameters of the industry.Without wishing to be tied to a particular theory, it is theorized thatutilization of a separate tacking process and bonding process canfacilitate improved production rates over single step attaching andbonding processes, such as conventional electroplating processes.

Abrasive articles of the embodiments herein have demonstrated improvedabrasive particle retention during use as compared to conventionalabrasive wire saws without at least one of the features of theembodiments herein. For example, the abrasive articles have an abrasiveparticle retention of at least about 2% improvement over one or moreconventional samples. In still other instances, the abrasive particleretention improvement can be at least about 4%, at least about 6%, atleast about 8%, at least about 10%, at least about 12%, at least about14%, at least about 16%, at least about 18%, at least about 20%, atleast about 24%, at least about 28%, at least about 30%, at least about34%, at least about 38%, at least about 40%, at least about 44%, atleast about 48%, or even at least about 50%. Still, in one non-limitingembodiment, the abrasive particle retention improvement can be notgreater than about 100%, such as not greater than about 95%, not greaterthan about 90%, or even not greater than about 80%.

Abrasive articles of the embodiments herein have demonstrated improvedabrasive particle retention and further demonstrated improved useablelife compared to conventional abrasive wire saws without at least one ofthe features of the embodiments herein. For example, the abrasivearticles herein can have an improvement of useable life of at leastabout 2% compared to one or more conventional samples. In still otherinstances, the increase in useable life of an abrasive article of anembodiment herein compared to a conventional article can be at leastabout 4%, at least about 6%, at least about 8%, at least about 10%, atleast about 12%, at least about 14%, at least about 16%, at least about18%, at least about 20%, at least about 24%, at least about 28%, atleast about 30%, at least about 34%, at least about 38%, at least about40%, at least about 44%, at least about 48%, or even at least about 50%.Still, in one non-limiting embodiment, the useable life improvement canbe not greater than about 100%, such as not greater than about 95%, notgreater than about 90%, or even not greater than about 80%.

Many different aspects and embodiments are possible. Some of thoseaspects and embodiments are described herein. After reading thisspecification, skilled artisans will appreciate that those aspects andembodiments are only illustrative and do not limit the scope of thepresent invention. Embodiments may be in accordance with any one or moreof the embodiments as listed below.

Embodiment 1

An abrasive article comprising:

-   -   a substrate comprising an elongated body;    -   a plurality of discrete tacking regions defining a discontinuous        distribution of features overlying the substrate, wherein at        least one discrete tacking region of the plurality of discrete        tacking regions comprises a metal material having a melting        temperature not greater than 450° C.;    -   a plurality of discrete formations overlying the substrate and        spaced apart from the plurality of discrete tacking regions; and    -   a bonding layer overlying the substrate, plurality of discrete        tacking regions, and plurality of discrete formations.

Embodiment 2

An abrasive article comprising:

-   -   a substrate comprising an elongated body;    -   a plurality of discrete tacking regions comprising a metal        material overlying the substrate, wherein at least one discrete        tacking region is isolated from another discrete tacking region,        and at least one abrasive particle is associated with at least        one discrete tacking region; and    -   a bonding layer overlying the plurality of discrete tacking        regions, the at least one abrasive particle and in direct        contact with at least a portion of the substrate.

Embodiment 3

An abrasive article comprising:

-   -   a substrate comprising an elongated body;    -   a plurality of discrete tacking regions overlying the substrate        and defining gap regions between each of the discrete tacking        regions of the plurality of discrete tacking regions;    -   abrasive particles overlying the plurality of discrete tacking        regions; and    -   a plurality of discrete formations overlying the substrate and        spaced apart from the plurality of discrete tacking regions and        the abrasive particles.

Embodiment 4

The abrasive article of any one of embodiments 2 and 3, wherein theplurality of discrete tacking regions include a metal material havingmelting temperature not greater than 450° C.

Embodiment 5

The abrasive article of any one of embodiments 1 and 4, wherein theplurality of discrete tacking regions include a metal material havingmelting temperature of at least 100° C.

Embodiment 6

The abrasive article of any one of embodiments 1, 2, and 3, wherein atleast one of the discrete tacking regions of the plurality of discretetacking regions comprises a metal material comprising an alloy oftransition metal elements, wherein at least one of the discrete tackingregions further comprises a metal selected from the group of metalsconsisting of lead, silver, copper, zinc, titanium, molybdenum,chromium, iron, manganese, cobalt, niobium, tantalum, tungsten,palladium, platinum, gold, ruthenium, and a combination thereof, whereinat least one of the discrete tacking regions comprises a metal alloy oftin, wherein at least one of the discrete tacking regions comprises asolder material.

Embodiment 7

The abrasive article of embodiment 6, wherein the solder materialcomprises tin.

Embodiment 8

The abrasive article of embodiment 6, wherein the solder materialconsists essentially of tin.

Embodiment 9

The abrasive article of embodiment 2, further comprising a plurality ofdiscrete formations overlying the substrate and spaced apart from theplurality of discrete tacking regions.

Embodiment 10

The abrasive article of any one of embodiments 1, 3, and 9, wherein atleast one of the discrete formations of the plurality of discreteformations comprises a metal material.

Embodiment 11

The abrasive article of any one of embodiments 1, 3, and 9, wherein atleast one of the discrete formations of the plurality of discreteformations includes a metal material having melting temperature of atleast 100° C. and not greater than 450° C.

Embodiment 12

The abrasive article of any one of embodiments 1, 3, and 9, wherein atleast one of the discrete formations of the plurality of discreteformations comprises a solder material.

Embodiment 13

The abrasive article of any one of embodiments 1, 3, and 9, wherein atleast one of the discrete formations of the plurality of discreteformations comprises tin.

Embodiment 14

The abrasive article of any one of embodiments 1, 3, and 9, wherein eachof the discrete formations of the plurality of discrete formationscomprises a solder material.

Embodiment 15

The abrasive article of any one of embodiments 1, 3, and 9, wherein atleast one of the discrete formations of the plurality of discreteformations comprises substantially the same material as a material ofthe plurality of discrete tacking regions.

Embodiment 16

The abrasive article of any one of embodiments 1, 3, and 9, wherein eachof the discrete formations is directly bonded to the substrate.

Embodiment 17

The abrasive article of any one of embodiments 1, 3, and 9, wherein theplurality of discrete formations are randomly distributed on the surfaceof the substrate.

Embodiment 18

The abrasive article of any one of embodiments 1, 3, and 9, furthercomprising gap regions extending between and separating the plurality ofdiscrete formations from each other and further separating the pluralityof discrete formations from the plurality of discrete tacking regions.

Embodiment 19

The abrasive article of any one of embodiments 1, 3, and 9, wherein theplurality of discrete formations have a generally rounded shape.

Embodiment 20

The abrasive article of any one of embodiments 1, 2, and 3, wherein thesubstrate is essentially free of a barrier layer.

Embodiment 21

The abrasive article of any one of embodiments 1, 2, and 3, wherein thesubstrate is an uncoated wire.

Embodiment 22

The abrasive article of any one of embodiments 1, 2, and 3, wherein thesubstrate comprises a metal wire essentially free of any barrier layerson an exterior surface.

Embodiment 23

The abrasive article of any one of embodiments 1, 2, and 3, wherein thesubstrate comprises a metal wire having at least one barrier layeroverlying an exterior surface, wherein the barrier layer comprises ametal selected from the group of copper, brass, nickel or a combinationthereof.

Embodiment 24

The abrasive article of any one of embodiments 1, 2, and 3, wherein theplurality of discrete tacking regions are randomly distributed on thesurface of the substrate.

Embodiment 25

The abrasive article of any one of embodiments 1 and 2, furthercomprising abrasive particles overlying the plurality of discretetacking regions.

Embodiment 26

The abrasive article of any one of embodiments 3 and 25, wherein theabrasive particles comprise a material selected from the group ofoxides, carbides, nitrides, borides, oxynitrides, oxyborides, diamond,and a combination thereof.

Embodiment 27

The abrasive article of any one of embodiments 3 and 25, wherein theabrasive particles comprise a superabrasive material.

Embodiment 28

The abrasive article of any one of embodiments 3 and 25, wherein theabrasive particles comprise diamond.

Embodiment 29

The abrasive article of any one of embodiments 3 and 25, wherein theabrasive particles comprise a material having a Vickers hardness of atleast about 10 GPa.

Embodiment 30

The abrasive article of embodiment 3, further comprising a bonding layeroverlying the plurality of discrete tacking regions.

Embodiment 31

The abrasive article of any one of embodiments 1, 2, and 30, wherein atleast a portion of the bonding layer is directly bonded to thesubstrate.

Embodiment 32

The abrasive article of any one of embodiments 1, 2, and 30, wherein atleast a portion of the bonding layer is directly bonded to the substratein gap regions between the plurality of discrete tacking regions andplurality of discrete formations.

Embodiment 33

The abrasive article of any one of embodiments 1, 2, and 30, wherein atleast a portion of the bonding layer is directly bonded to the pluralityof discrete tacking regions and plurality of discrete formations.

Embodiment 34

The abrasive article of any one of embodiments 1, 2, and 30, wherein thebonding layer comprises a material selected from the group of materialsconsisting of metals, metal alloys, cermets, ceramics, composites, and acombination thereof, wherein the bonding layer comprises a transitionmetal element, wherein the bonding layer comprises an alloy oftransition metal elements, wherein the bonding layer comprises a metalselected from the group of metals consisting of lead, silver, copper,zinc, tin, titanium, molybdenum, chromium, iron, manganese, cobalt,niobium, tantalum, tungsten, palladium, platinum, gold, ruthenium, and acombination thereof, wherein the bonding layer comprises nickel, whereinthe bonding layer consists essentially of nickel.

Embodiment 35

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a content of metal material (Cmm) in the plurality ofdiscrete tacking regions and plurality of discrete formations, measuredas grams of the metal material per kilometer of the length of thesubstrate, wherein the content of metal material (Cmm) is not greaterthan 2 g/kmor not greater than 1 g/km or not greater than 0.8 g/km ornot greater than 0.6 g/km or not greater than 0.4 g/km or not greaterthan 0.2 g/km or not greater than 0.1 g/km or not greater than 0.08 g/kmor not greater than 0.06 g/km or not greater than 0.04 g/km or notgreater than 0.02 g/km or not greater than 0.01 g/km.

Embodiment 36

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a content of metal material (Cmm) in the plurality ofdiscrete tacking regions and plurality of discrete formations, measuredas grams of the metal material per kilometer of the length of thesubstrate, wherein the content of metal material (Cmm) is at least 0.001g/km or at least 0.002 g/km or at least 0.004 g/km or at least 0.006g/km or at least 0.008 g/km or at least 0.01 g/km or at least 0.02 g/kmor at least 0.04 g/km or at least 0.06 g/km or at least 0.08 g/km or atleast 0.01 g/km.

Embodiment 37

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a content of abrasive particles (Cap) as measured in gramsper kilometer of length of the substrate and a content of metal material(Cmm) in the plurality of discrete tacking regions and plurality ofdiscrete formations as measured in grams per kilometer of length of thesubstrate, and further comprising a ratio (Cmm/Cap) of not greater than1 or not greater than 0.9 or not greater than 0.8 or not greater than0.7 or not greater than 0.6 or not greater than 0.5 or not greater than0.4 or not greater than 0.3 or not greater than 0.2 or not greater than0.18 or not greater than 0.16 or not greater than 0.15 or not greaterthan 0.014 or not greater than 0.13 or no greater than 0.12 or notgreater than 0.11 or not greater than 0.1 or not greater than 0.09 ornot greater than 0.08 or not greater than 0.07 or not greater than 0.06or no greater than 0.05 or not greater than 0.04 or not greater than0.03 or not greater than 0.02.

Embodiment 38

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a content of abrasive particles (Cap) as measured in gramsper kilometer of length of the substrate and a content of metal material(Cmm) in the plurality of discrete tacking regions and plurality ofdiscrete formations as measured in grams per kilometer of length of thesubstrate, and further comprising a ratio (Cmm/Cap) of at least 0.002 orat least 0.004 or at least 0.006 or at least 0.008 or at least 0.01 orat least 0.02 or at least 0.03 or at least 0.04 or at least 0.05 or atleast 0.06 or at least 0.07 or at least 0.08 or at least 0.09 or atleast 0.1 or at least 0.12 or at least 0.14 or at least 0.16 or at least0.18 or at least 0.2 or at least 0.3 or at least 0.4 or at least 0.5 orat least 0.6 or at least 0.7 or at least 0.8 or at least 0.9.

Embodiment 39. The abrasive article of any one of embodiments 1, 2, and3, further comprising an abrasive particle concentration of at least 10particles per mm of substrate, at least 20 particles per mm ofsubstrate, at least 30 particles per mm of substrate, and not greaterthan 800 particles per mm of substrate.

Embodiment 40

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising an abrasive particle concentration of at least about 0.5carats per kilometer of the substrate, at least about 1.0 carats perkilometer of substrate, of at least about 1.5 carats per kilometer ofsubstrate, not greater than about 30.0 carats per kilometer ofsubstrate.

Embodiment 41

A method of forming an abrasive article comprising:

-   -   translating a substrate having an elongated body through a        mixture including abrasive particles and a particulate including        a tacking material;    -   attaching at least a portion of the abrasive particles and        particulate to the substrate; and    -   treating the substrate to form an abrasive article preform        including:    -   a plurality of discrete tacking regions overlying the substrate        and defining gap regions between each of the discrete tacking        regions of the plurality of discrete tacking regions;    -   abrasive particles overlying the plurality of discrete tacking        regions; and    -   a plurality of discrete formations overlying the substrate and        spaced apart from the plurality of discrete tacking regions and        the abrasive particles.

Embodiment 42

The method of embodiment 41, wherein the mixture includes at least 5 wt% and not greater than 80 wt % of the abrasive particles for the totalweight of the mixture.

Embodiment 43

The method of embodiment 41, wherein the mixture includes at least 0.2wt % to not greater than 20 wt % of the particulate including thetacking material for the total weight of the mixture.

Embodiment 44

The method of embodiment 41, wherein the abrasive particles have anaverage particle size (PS a) within a range including at least 2 micronsand not greater than 80 microns.

Embodiment 45

The method of embodiment 41, wherein the particulate comprises anaverage particles size (PSp) within a range including at least 0.01microns and not greater than 25 microns.

Embodiment 46

The method of embodiment 41, wherein the abrasive particles have anaverage particle size (PS a) and the particulate comprises an averageparticles size (PSp), and wherein the mixture includes a ratio (PSp/PSa)of not greater than 1 or not greater than 0.9 or not greater than 0.8 ornot greater than 0.7 or not greater than 0.6 or not greater than 0.5 ornot greater than 0.4 or not greater than 0.3 or not greater than 0.2 ornot greater than 0.18 or not greater than 0.16 or not greater than 0.15or not greater than 0.014 or not greater than 0.13 or no greater than0.12 or not greater than 0.11 or not greater than 0.1 or not greaterthan 0.09 or not greater than 0.08 or not greater than 0.07 or notgreater than 0.06 or no greater than 0.05 or not greater than 0.04 ornot greater than 0.03 or not greater than 0.02.

Embodiment 47

The method of embodiment 41, wherein the abrasive particles have anaverage particle size (PS a) and the particulate comprises an averageparticles size (PSp), and wherein the mixture includes a ratio (PSp/PSa)of at least 0.01 or at least 0.02 or at least 0.03 or at least 0.04 orat least 0.05 or at least 0.06 or at least 0.07 or at least 0.08 or atleast 0.09 or at least 0.1 or at least 0.11 or at least 0.12 or at least0.13 or at least 0.14 or at least 0.15 or at least 0.16 or at least 0.17or at least 0.18 or at least 0.19 or at least 0.2 or at least 0.3 or atleast 0.4 or at least 0.5 or at least 0.6 or at least 0.7 or at least0.8 or at least 0.9.

Embodiment 48

The method of embodiment 41, wherein treating includes heating thepreform to a temperature within a range including at least 100° C. andnot greater than 450° C.

Embodiment 49

The method of embodiment 41, wherein the mixture includes flux.

Embodiment 50

The method of embodiment 41, wherein the mixture is a slurry comprisinga carrier for the abrasive particles and particulate, the carrierincluding water.

Embodiment 51

The method of embodiment 41, further comprising forming a bonding layeroverlying the substrate and abrasive particles, wherein the bondinglayer is formed by a deposition process, wherein the deposition processis selected from the group consisting of plating, electroplating,dipping, spraying, printing, coating, and a combination thereof.

Embodiment 52

The method of embodiment 41, wherein the process of attaching includesattaching the abrasive particles and particulate from a mixture at atemperature within a range including at least 1° C. and not greater than300° C.

Embodiment 53

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a ratio (PSp/PSa) of at least about 0.025 and not greaterthan about 0.25.

Embodiment 54

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a ratio (Cp/Cap) of at least about 0.025 and not greater thanabout 0.25.

Embodiment 55

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a ratio (Cmm/Cap)of at least 0.002 and not greater than 1, atleast 0.01 and not greater than 0.5 and at least 0.025 and not greaterthan 0.25.

Embodiment 56

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a TMc of not greater than about 50%, not greater than about45%, not greater than about 40%, not greater than about 35%, not greaterthan about 30%, not greater than about 25%, not greater than about 20%,not greater than about 15%, not greater than about 10% and not greaterthan about 5%.

Embodiment 57

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising a TMc of at least about 0.01%, at least about 0.1% and atleast about 1.%.

Embodiment 58

The abrasive article of any one of embodiments 1, 2, and 3, furthercomprising an APsa of not greater than about 60%, such as, not greaterthan about 50%, not greater than about 40%, not greater than about 30%,not greater than about 20% or even not greater than about 10%.

EXAMPLE 1:

A length of high strength carbon steel wire is obtained as a substrate.The high strength carbon steel wire has a brass coating layer and anaverage diameter of approximately 175 microns. The wire is translatedthrough a mixture including about 40 wt % diamond commercially availableas 20% Ni coated micron diamond from ABC Warren Superabrasives having anaverage particle size of about 35 micrometers, and about 2 wt % of tinparticulate material commercially available as SN-101 tin powder fromAtlantic Equipment Engineers having an average particle size of 1-5micrometers, and about 10 wt % of additives including ZnCl flux. Themixture also included an additive in the form of a viscosity modifier,which was present in an amount sufficient to make the mixture with aviscosity of 3-5 centipoise at room temperature. The wire is translatedat a rate of approximately 20 to 30 m/min.

The diamond, particulate, and flux are attached to the wire as it wasdrawn vertically from the mixture and the structure is heated at atemperature within a range of 220 to 280 degree Celsius for a durationof 0.2 to 0.5 seconds to form an abrasive article preform.

Thereafter, the abrasive article preform is washed using 10% sulfamicacid followed by a rinse with de-ionized water. The rinsed article iselectroplated with nickel to form a bonding layer directly contactingand overlying the abrasive particles and portions of the substrate.FIGS. 4-6 include images of the abrasive article formed from the processof Example

EXAMPLE 2

A sample abrasive wire S1 was formed according to embodiments describedherein. For sample abrasive wire S1, a length of high strength carbonsteel wire was obtained as a substrate. Diamond grains having an averageparticle size of between 30 microns to 50 microns were attached to thewire according to embodiments described herein using discrete Sn tackingregions (i.e., a discontinuous distribution of tacking material on thesurface of the wire). The diamond grains, discrete Sn tacking regionsand exposed wire surface were cleaned and coated with a Ni bonding layerhaving a thickness of 10 microns. FIG. 7A includes a cross-sectionalimage of the sample abrasive wire S1.

For purposes of comparison, a comparative sample abrasive wire CS1 wasformed. For comparative sample abrasive wire CS1, a length of highstrength carbon steel wire was obtained as a substrate. Diamond grainshaving an average particle size of between 30 microns to 50 microns wereattached to the wire using a continuous layer of Sn tacking material.The diamond grains and Sn tacking layer were cleaned and coated with Nibonding layer having a thickness of 10 microns. FIG. 7B includes a crosssectional image of the sample abrasive wire S1.

A coating adhesion test was performed according to the experimentalsetup shown in FIG. 8. As shown in in FIG. 8, a sample abrasive wire 800(e.g., sample abrasive wire S1 or CS1) is pulled through two clamps 810having jaw faces 815. The jaw faces 815 are angled so that their upperedges contact the sample abrasive wire 800. The clamping pressure isthen systematically increased using a pneumatic controller as the sampleabrasive wire 800 is pulled through the two clamps 810 in order toevaluate the adhesion strength of the Ni bonding on the sample abrasivewire 800.

For comparative sample abrasive wire CS1, the Ni bonding was removedfrom the surface of the abrasive wire at a clamping pressure of 20 psi.FIG. 9A includes an image of the comparative sample abrasive wire CS1after the adhesion test showing the Ni bonding removed from the surfaceof the wire.

The Ni bonding of sample abrasive wire Si remained adhered to thesurface of the wire at a clamping pressure of 20 psi. FIG. 9B includesan image of the sample abrasive wire Si after the adhesion test, showingan intact Ni bonding layer with only small scratches on the coatingsurface. As shown through the comparison of FIGS. 9A and 9B, the Nibonding on abrasive wire sample S1 had better adhesion to the substratethan Ni bonding on the comparative abrasive wire sample CS1.

EXAMPLE 3

A sample abrasive wire S2 was formed according to embodiments describedherein. For sample abrasive wire S2, a length of high strength carbonsteel wire is obtained as a substrate. Diamond grains having an averageparticle size of between 8 microns to 12 microns were attached to thewire according to embodiments described herein using discrete Sn tackingregions (i.e., a discontinuous distribution of tacking material on thesurface of the wire). The diamond grains, discrete Sn tacking regionsand exposed wire surface were cleaned and coated with nickel bondinglayer having a thickness of 4 microns.

For purposes of comparison, a comparative sample abrasive wire CS2 wasformed. For comparative sample abrasive wire CS2, a length of highstrength carbon steel wire is obtained as a substrate. Diamond grainshaving an average particle size of between 8 microns to 12 microns wereattached to the wire using a continuous layer Sn tacking material. Thediamond grains and Sn tacking layer were cleaned and coated with Nibonding layer having a thickness of 4 microns.

A silicon cutting test was performed on a Meyer Burger DS 271 wire saw.Testing conditions are listed in Table 1 below:

TABLE 1 Cutting Test Performance Parameters Work Material monocrystalline silicon with the dimension of 125 × 125 mm pseudo squareWire Tension 22 N Maximum Wire Speed 18 m/s Feed Rate 0.75 mm/minCoolant 22 N

Wire bow performance for sample abrasive wire S2 and comparative sampleabrasive wire CS2 was measured at 4 different locations across the 200mm silicon ingot. FIG. 10 includes a plot of the steady state wire bowfor sample abrasive wire S2 and comparative sample abrasive wire CS2 atthe 4 measurement locations. Generally, smaller steady state wire bow ispreferred in wire saw performance as it suggests more effective cuttingon the work material. As shown in FIG. 10, sample abrasive wire S2produced smaller steady state wire bow than comparative sample abrasivewire CS2 at all four measurement locations across the workpiece.

EXAMPLE 4

Three sample abrasive wires S3, S4 and S5 were formed using a dipcoating process.

Sample abrasive wire S3 was formed using a brass coated steel wirehaving a thickness of approximately 100 microns. The wire was pretreatedwith a 6% hydrochloride solution to remove excess oxide on the surfaceof the wire. The core wire was then dip coated through a slurry mixtureof 5 grams of 2-5 micron Sn powder, 100 grams of 8-16 micron diamondgrains, hydrochloride, zinc chloride, glycerine and water. The coatedwire was then heated to attach the diamond grains to the wire and washedwith a hot acid and water bath. The coated wire was then electroplatedwith a nickel bonding layer having a thickness of 4 microns.

Due to insufficient tacking material in the slurry, minimal diamondgrains were successfully tacked to the sample abrasive wire S3, whichultimately made the wire unusable.

Sample abrasive wire S4 was formed using a brass coated steel wirehaving a thickness of approximately 100 microns. The wire was pretreatedwith a 6% hydrochloride solution to remove excess oxide on the surfaceof the wire. The core wire was then dip coated through a slurry mixtureof 40 grams of 2-5 micron Sn powder, 100 grams of 8-16 micron diamondgrains, hydrochloride, zinc chloride, glycerine and water. The coatedwire was then heated to attach the diamond grains to the wire and washedwith a hot acid and water bath. The coated wire was then electroplatedwith a nickel bonding layer having a thickness of 4 microns.

A visual inspection of sample abrasive wire S4 showed that diamondgrains were successfully attached to the wire and coated withelectroplated nickel. FIG. 11A includes a surface SEM image of sampleabrasive wire S4. As shown in FIG. 11A, agglomerations of diamond grainswere observed. Without wishing to be tied to any particular theory, itis believed that agglomeration of the diamond grains occurred due tonon-optimal Sn powder particle size and non-optimal Sn powderconcentration in the slurry.

Sample abrasive wire S5 was formed using a brass coated steel wirehaving a thickness of approximately 100 microns. The wire was pretreatedwith a 6% hydrochloride solution to remove excess oxide on the surfaceof the wire. The core wire was then dip coated through a slurry mixtureof 10 grams of 1-2 micron Sn powder, 100 grams of 8-16 micron diamondgrains, hydrochloride, zinc chloride, glycerine and water. The coatedwire was then heated to attach the diamond grains to the wire and washedwith a hot acid and water bath. The coated wire was then electroplatedwith a nickel bonding layer having a thickness of 4 microns.

A visual inspection of sample abrasive wire S5 showed that diamondgrains were successfully attached to the wire and coated withelectroplated nickel. FIG. 11B includes a surface SEM image of sampleabrasive wire S4. As shown in FIG. 11B, diamond grains were distributeduniformly on the surface of the wire with little agglomeration.

For purposes of comparison, the ratio PSp/PSa, the ratio Cp/Cap, theratio Cmm/Cap, the TMc and the APsa were measured and calculatedaccording to procedures described herein for sample abrasive wires S4and S5. The results of these measurements for sample abrasive wires S4and S5 are summarized in Table 2 below:

TABLE 2 Sample Measurements Measurement/Ratio S4 S5 PSp/PSa 0.29 0.125Cp/Cap 0.4 0.1 Cmm/Cap 0.4 0.1 TMc 70% 10% APsa 60% 10%

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples are illustrative only and not intended to be limiting. To theextent not described herein, many details regarding specific materialsand processing acts are conventional and may be found in reference booksand other sources within the structural arts and correspondingmanufacturing arts.

The above-disclosed subject matter is to be considered illustrative, andnot restrictive, and the appended claims are intended to cover all suchmodifications, enhancements, and other embodiments, which fall withinthe true scope of the present invention. Thus, to the maximum extentallowed by law, the scope of the present invention is to be determinedby the broadest permissible interpretation of the following claims andtheir equivalents, and shall not be restricted or limited by theforegoing detailed description.

The Abstract of the Disclosure is provided to comply with Patent Law andis submitted with the understanding that it will not be used tointerpret or limit the scope or meaning of the claims. In addition, inthe foregoing Detailed Description of the Drawings, various features maybe grouped together or described in a single embodiment for the purposeof streamlining the disclosure. This disclosure is not to be interpretedas reflecting an intention that the claimed embodiments require morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter may be directed toless than all features of any of the disclosed embodiments. Thus, thefollowing claims are incorporated into the Detailed Description of theDrawings, with each claim standing on its own as defining separatelyclaimed subject matter.

What is claimed is:
 1. An abrasive article comprising: a substratecomprising an elongated body; a plurality of discrete tacking regionsoverlying the substrate and defining gap regions between each of thediscrete tacking regions of the plurality of discrete tacking regions;abrasive particles overlying the plurality of discrete tacking regions;and a plurality of discrete formations overlying the substrate andspaced apart from the plurality of discrete tacking regions and theabrasive particles.
 2. The abrasive article of claim 1, wherein at leastone of the discrete tacking regions further comprises a metal selectedfrom the group of metals consisting of lead, silver, copper, zinc,titanium, molybdenum, chromium, iron, manganese, cobalt, niobium,tantalum, tungsten, palladium, platinum, gold, ruthenium, and acombination thereof.
 3. The abrasive article of claim 1, wherein atleast one of the discrete formations of the plurality of discreteformations comprises substantially the same material as a material ofthe plurality of discrete tacking regions.
 4. The abrasive article ofclaim 1, wherein each of the discrete formations is directly bonded tothe substrate.
 5. The abrasive article of claim 1, wherein the pluralityof discrete formations are randomly distributed on the surface of thesubstrate.
 6. The abrasive article of claim 1, further comprising gapregions extending between and separating the plurality of discreteformations from each other and further separating the plurality ofdiscrete formations from the plurality of discrete tacking regions. 7.The abrasive article of claim 1, wherein the plurality of discreteformations have a generally rounded shape.
 8. The abrasive article ofclaim 1, wherein the substrate is essentially free of a barrier layer.9. The abrasive article of claim 1, wherein the substrate is an uncoatedwire.
 10. The abrasive article of claim 1, wherein the substratecomprises a metal wire essentially free of any barrier layers on anexterior surface.
 11. The abrasive article of claim 1, wherein thesubstrate comprises a metal wire having at least one barrier layeroverlying an exterior surface, wherein the barrier layer comprises ametal selected from the group of copper, brass, nickel or a combinationthereof.
 12. The abrasive article of claim 1, wherein the plurality ofdiscrete tacking regions are randomly distributed on the surface of thesubstrate.
 13. The abrasive article of claim 1, further comprisingabrasive particles overlying the plurality of discrete tacking regions.14. The abrasive article of claim 1, wherein the abrasive particlescomprise a material selected from the group of oxides, carbides,nitrides, borides, oxynitrides, oxyborides, diamond, and a combinationthereof.
 15. The abrasive article of claim 1, wherein the abrasiveparticles comprise a superabrasive material.
 16. The abrasive article ofclaim 1, wherein the abrasive particles comprise diamond.
 17. Theabrasive article of claim 1, wherein the abrasive particles comprise amaterial having a Vickers hardness of at least about 10 GPa.
 18. Theabrasive article of claim 1, further comprising a bonding layeroverlying the plurality of discrete tacking regions.
 19. The abrasivearticle of claim 18, wherein at least a portion of the bonding layer isdirectly bonded to the substrate.
 20. The abrasive article of claim 18,wherein at least a portion of the bonding layer is directly bonded tothe substrate in gap regions between the plurality of discrete tackingregions and plurality of discrete formations.